Barley and wide vetch mixed sowing method

Abstract

The invention provides a barley and wide vetch mixed sowing method, and belongs to the technical field of crop mixed cropping. The method comprises the following steps: (1) airing seeds of barley and vetch for 2-3 days, and dressing the seeds to obtain pretreated seeds; (2) sowing the pretreated seeds into the pretreated land in a same-row mixed sowing mode or an inter-row mixed sowing mode, and performing field management and harvesting to obtain barley and wide vetch; during mixed sowing in the same row, the mixing ratio of the barley to the wide vetch is 100-140 kg / hm < 2 >: 10-20 kg / hm < 2 >. According to the mixed sowing method provided by the invention, passive consumption of soil nutrients can be changed into active fertilization, a new mode of cultivating land while producing is formed, a low-cost and biological-source soil acidification improvement alternative scheme is further provided, and the method can reduce dependence on lime.

Description

Technical Field

[0001] This invention relates to the field of crop intercropping technology, and more particularly to a method for intercropping barley and wild pea. Background Technology

[0002] Agricultural ecosystems are facing the dual challenges of maintaining high yields and protecting the environment, requiring modern agriculture to develop in a more sustainable direction. Intercropping, as a classic ecological intensive planting model, can significantly improve the utilization efficiency of resources such as light, heat, water, and fertilizer through the complementary effects between species. Among them, grass-legume intercropping is widely regarded as one of the most efficient models, showing great potential in improving land productivity, reducing fertilizer input, and improving soil ecological functions.

[0003] The core advantage of intercropping systems of grasses and legumes lies in the biological nitrogen fixation of legumes. This ability allows nitrogen to be introduced into the system through rhizosphere deposition and other pathways, thus partially replacing chemical nitrogen fertilizers and potentially benefiting the accompanying grasses. Studies have shown that under conditions of sufficient root interaction, the nitrogen uptake of a barley-pea intercropping system can be increased by 81.1% compared to root-separated treatments. The introduction of legumes not only improves soil fertility and productivity but also helps maintain the biodiversity and stability of agro-ecosystems.

[0004] Interspecific relationships in intercropping of grasses and legumes form a crucial biological basis for high yields and efficient resource utilization. Legumes can supply nitrogen in a more slow-release and sustained manner through biological nitrogen fixation, which can reduce the dominance of species with high fertility in the community to some extent, thus benefiting species coexistence and the maintenance of diversity. Simultaneously, legume litter is high in quality and decomposes rapidly, accelerating nutrient cycling and quickly improving soil fertility. Grasses, on the other hand, primarily absorb nitrogen from the soil through competition, stimulating the nitrogen-fixing potential of legumes. This complementary mechanism gives intercropping systems a significant advantage in increasing crop yields and nitrogen use efficiency. Research by Zhao Yanhua (Zhao Yanhua. The impact of increased density on the ecological processes of maize / pea productivity formation and greenhouse gas emissions [D]. Gansu Agricultural University, 2020. DOI:10.27025 / d.cnki.ggsnu.2020.000002.) shows that the yield of maize / pea intercropping systems is 34.0%-37.9% higher than the weighted average yield of the corresponding monoculture, and the system has the potential to reduce greenhouse gas emissions.

[0005] Although the value of intercropping between cereals and legumes is widely recognized, and significant interactions between nitrogen application, root interactions, and density have been observed in barley-pea systems, systematic research on the specific combination of barley and *Vicia favabilis*, especially on the precise control of various intercropping ratios under different spatial configurations, remains insufficient. Most existing studies either focus on a single configuration or have limited gradients in intercropping ratios, failing to fully reveal the synergistic effects of the fine-grained interaction mechanism of "spatial configuration × intercropping ratio" on system productivity and soil fertility. Furthermore, the optimal intercropping ratio varies depending on the species combination and region. For example, in the Lhasa River Valley, 'Zhongsi 828' triticale and *Vicia favabilis* show good interspecific compatibility when intercropped at 6:4 and 3:7 ratios, while the optimal intercropping ratio for *Leymus chinensis*-alfalfa combination is 1:1. Therefore, it is necessary to systematically explore the optimal configuration patterns for the specific combination of barley and *Vicia favabilis*. Summary of the Invention

[0006] The purpose of this invention is to provide a method for intercropping barley and pea, which can save land resources, increase the yield and quality of barley and pea, improve the soil environment, achieve sustainable nitrogen cycling, and improve soil acidification.

[0007] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a method for intercropping barley and widespread wild pea, comprising the following steps: (1) Dry the seeds of barley and wild pea for 2-3 days, then mix them with water to obtain pretreated seeds; (2) Sow the pretreated seeds in the pretreated land in the form of mixed planting in the same row or between rows, manage the field, harvest, and obtain barley and peas. The mixing ratio of barley and broad-based wild vetch in the same row is 100-140 kg / hm². 2 10-20 kg / hm 2 .

[0008] Preferably, in step (1), the barley is characterized by a plant height of 80-120cm, a stem thickness of 3-5mm, and 4-10 tillers; the widely distributed wild pea is characterized by a climbing height of 80-120cm and 10-20 branches.

[0009] Preferably, in step (1), the drying method is natural drying; the agent used in the seed dressing is phorate, and the effective concentration of phorate is 3%-5%.

[0010] Preferably, in step (1), the application rate of phorate is 1.5-2.5 kg / mu.

[0011] More preferably, in step (1), the seed mixing process also includes fine soil, and the amount of fine soil added is 1-2 kg / mu.

[0012] Preferably, in step (1), the seed mixing is carried out in the dark.

[0013] Preferably, in step (2), the mixing ratio of barley and wild pea during intercropping is 80-100 kg / hm. 2 20-25 kg / hm 2 .

[0014] Preferably, in step (2), the sowing method is row sowing, the sowing depth is 3-5cm, and the row spacing is 28-32cm.

[0015] Preferably, in step (2), the sowing time is from early October to mid-November, and barley and wild pea are sown at the same time; the pretreated land meets the standards of "even, flat, loose, broken, clean and moist".

[0016] Preferably, in step (2), the field management includes water and fertilizer management and pest and disease control; the harvesting period is the barley wax ripening period.

[0017] The beneficial effects of this invention compared to the prior art are as follows: This invention systematically analyzed the comprehensive performance of barley-wide wild vetch under different intercropping configurations. The T2 treatment group (row-to-row intercropping, grass:vetch = 2:1) showed the best performance, with a land equivalent ratio of 1.48 and a land saving efficiency of 32.4%. Its total dry matter yield reached 23167.52 kg / hm², significantly better than other treatments; its total crude protein yield reached 2920.29 kg / hm², an increase of 27.1% compared to monoculture; and its total relative yield was 2.99, significantly higher than other treatments. The J1 treatment group (intercropping, grass:vetch = 1:1) significantly improved the cell wall structure of barley, with neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents of 53.51% and 33.23%, respectively, improving the palatability and digestibility of the forage. Treatments T2 and J1 showed significant fertilization effects, with organic matter content reaching 19.18 and 18.51 g / kg, respectively, representing increases of 66.5% and 60.7% compared to the control (CK). Total nitrogen content was 1.47 and 1.25 g / kg, respectively, representing increases of 54.7% and 31.6%. They also demonstrated significant pH regulation capabilities, improving soil pH and alleviating acidification issues. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 The diagram illustrates the sowing of barley and pea, where, in treatment T1, the sowing rates are: barley: 90 kg / hm². 2 Widespread wild pea: 22.5 kg / hm 2 The number of seeds was calculated based on the thousand-grain weight: 2,000,000 barley seeds and 900,000 pea seeds, with a seed ratio of approximately 2:1 (barley:pea). In treatment T2, the sowing rates were: barley: 120 kg / hm². 2 Wild peas: 15 kg / hm 2 Based on the thousand-grain weight, the number of seeds was calculated as follows: barley 2,666,667 seeds, and pea 600,000 seeds. The seed ratio was approximately 4:1 (barley:pea). In treatment T3, the sowing rate was 60 kg / hm² for barley. 2 Wild peas: 30 kg / hm 2 Based on the thousand-grain weight, the number of seeds was calculated as follows: barley 1,333,333 seeds, and pea seed 1,200,000 seeds. The seed ratio was approximately 1:1 for barley and pea. In treatment J1, the sowing rate was 90 kg / hm² for barley. 2 Widespread wild pea: 22.5 kg / hm 2 The number of seeds was calculated based on the thousand-grain weight: 2,000,000 barley seeds and 900,000 pea seeds, with a seed ratio of approximately 2:1 (barley:pea). In treatment J2, the sowing rates were: barley: 120 kg / hm². 2 Wild peas: 15 kg / hm 2 Based on the thousand-grain weight, the number of seeds was calculated as follows: barley 2,666,667 seeds, and pea 600,000 seeds. The seed ratio was approximately 2:1 (barley:pea). In treatment J3, the sowing rate was 60 kg / hm² for barley. 2 Wild peas: 30 kg / hm 2 The number of seeds was calculated based on the weight of 1,000 seeds. There were 1,333,333 barley seeds and 1,200,000 pea seeds. The seed ratio was approximately 4:1 for barley and 1 pea. Detailed Implementation

[0020] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0021] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0022] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0023] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0024] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0025] This invention provides a method for intercropping barley and widespread wild pea, comprising the following steps: (1) Dry the seeds of barley and wild pea for 2-3 days, then mix them with water to obtain pretreated seeds; (2) Sow the pretreated seeds in the pretreated land in the form of mixed planting in the same row or between rows, manage the field, harvest, and obtain barley and peas. The mixing ratio of barley and broad-based wild vetch in the same row is 100-140 kg / hm². 2 10-20 kg / hm 2 .

[0026] In step (1) of this invention, the barley is preferably characterized by a plant height of 80-120cm, a stem thickness of 3-5mm, and 4-10 tillers; the plant height is further preferably 90-110cm, and even more preferably 100cm; the stem thickness is further preferably 3.5-4.5mm, and even more preferably 4mm; the number of tillers is further preferably 5-8, and even more preferably 6. The widely distributed wild pea is preferably characterized by a climbing height of 80-120cm and 10-20 branches; the climbing height is further preferably 90-110cm, and even more preferably 10-20 branches. 00cm; the number of branches is further preferably 14-18, and even more preferably 15; the drying method is preferably natural drying; the agent used in seed dressing is preferably phorate, and the effective concentration of phorate is preferably 3%-5%, and even more preferably 4%; the application rate of phorate is preferably 1.5-2.5 kg / mu, and even more preferably 2 kg / mu; the seed dressing also preferably includes fine soil, and the amount of fine soil added is preferably 1-2 kg / mu, even more preferably 1.4-1.8 kg / mu, and even more preferably 1.5 kg / mu; the seed dressing is preferably carried out in the dark.

[0027] In step (2) of this invention, the mixing ratio of barley and wild pea during the parallel planting is 100-140 kg / hm. 2 10-20 kg / hm 2 A further preferred value is 110-130 kg / hm. 2 14-18 kg / hm 2 A further preferred value is 120 kg / hm. 2 15kg / hm 2 The method of inter-row mixed sowing involves sowing within the same row, with a row spacing of 30cm for barley and 30cm for pea. The preferred mixing ratio of barley to pea in inter-row mixed sowing is 80-100 kg / hm². 2 20-25 kg / hm 2 Further preferred is 85-95 kg / hm 2 22-24 kg / hm 2 A further preferred value is 90 kg / hm 2 22.5 kg / hm 2The inter-row sowing method involves alternating rows of barley and peas, with a row spacing of 30cm for both barley and peas. The preferred sowing method is row sowing, with a sowing depth of 3-5cm, more preferably 4cm. The preferred row spacing is 28-32cm, more preferably 30cm. The preferred sowing time is from early October to mid-November, and barley and peas are preferably sown simultaneously. The pre-treated land should meet the standards of being even, level, loose, fine, clean, and moist. Field management preferably includes water and fertilizer management and pest and disease control. The preferred water and fertilizer management method is micro-sprinkler irrigation after sowing, keeping the soil moist before emergence to promote seedling growth. Special attention should be paid to the peas' intolerance to waterlogging, and water accumulation in the field should be avoided. The preferred harvesting time is the waxy ripening stage of barley, and barley and peas are preferably harvested simultaneously.

[0028] Example 1 A method for intercropping barley and widespread wild pea includes the following steps: (1) Select barley seeds with growth characteristics of plant height of 80-120cm, stem thickness of 3-5mm, and 4-10 tillers, and select seeds of widely distributed wild pea with growth characteristics of climbing height of 80-120cm, 10-20 branches, lush leaves and well-developed root system. After naturally drying for 2 days, mix them with 1kg / mu of fine soil mixed with 4% phoxim granules under the dark for seed treatment to obtain pretreated seeds; (2) In early October, barley pretreated seeds were mixed with pea pretreated seeds at a mixing ratio of 120 kg / hm. 2 15kg / hm 2 Sow the seeds in rows (within the same row) in pre-treated land that meets the standards of "evenness, flatness, looseness, fragmentation, cleanliness, and moisture". The sowing depth is 4 cm and the row spacing is 30 cm. After sowing, use micro-sprinkler irrigation. Keep the soil moist before emergence to promote seedling emergence. Pay special attention to the fact that Vitex aegypti is not tolerant of waterlogging. Avoid water accumulation in the field. Fertilize and irrigate throughout the growth period, and control diseases and pests. Harvest at the waxy ripening stage of barley to obtain barley and Vitex aegypti.

[0029] Example 2 A method for intercropping barley and widespread wild pea includes the following steps: (1) Select barley seeds with growth characteristics of plant height of 80-120cm, stem thickness of 3-5mm, and 4-10 tillers, and select seeds of widely distributed wild pea with growth characteristics of climbing height of 80-120cm, 10-20 branches, lush leaves and well-developed root system. After naturally drying for 3 days, mix them with 2kg / mu of fine soil mixed with 4% phoxim granules under the dark for seed treatment to obtain pretreated seeds; (2) In mid-November, barley pretreated seeds were mixed with pea pretreated seeds at a mixing ratio of 90 kg / hm. 2 22.5 kg / hm 2 Sow barley and peas alternately in rows using a row-sowing method (alternating between one row of barley and one row of peas) in pre-treated land that meets the standards of "evenness, levelness, looseness, fragmentation, cleanliness, and moisture." The sowing depth is 4 cm, and the row spacing is 30 cm. After sowing, use micro-sprinkler irrigation. Keep the soil moist before emergence to promote germination. Pay special attention to the fact that peas are not tolerant of waterlogging, and avoid water accumulation in the field. Fertilize and irrigate throughout the entire growth period, and control diseases and pests. Harvest barley at the waxy ripening stage to obtain barley and peas.

[0030] Example 3 A method for intercropping barley and widespread wild pea includes the following steps: (1) Select barley seeds with growth characteristics of plant height of 80-120cm, stem thickness of 3-5mm, and 4-10 tillers, and select seeds of widely distributed wild pea with growth characteristics of climbing height of 80-120cm, 10-20 branches, lush leaves and well-developed root system. After naturally drying for 2.5 days, mix them with 1.5kg / mu of fine soil mixed with 5% phoxim granules under the dark for seed treatment to obtain pretreated seeds; (2) In mid-October, barley pretreated seeds were mixed with pea pretreated seeds at a mixing ratio of 100 kg / hm. 2 10kg / hm 2 Sow the seeds in rows (within the same row) in pre-treated land that meets the standards of "evenness, levelness, looseness, fragmentation, cleanliness, and moisture". The sowing depth is 3cm and the row spacing is 28cm. After sowing, use micro-sprinkler irrigation. Keep the soil moist before emergence to promote germination. Pay special attention to the fact that Vitex aegypti is not tolerant of waterlogging. Avoid water accumulation in the field. Fertilize and irrigate throughout the growth period, and control diseases and pests. Harvest at the waxy ripening stage of barley to obtain barley and Vitex aegypti.

[0031] Experimental Example 1 1. Experimental Design The experiment employed a randomized block design with 8 treatments (as shown in Table 1), each with 3 replicates, for a total of 24 plots to minimize the impact of soil variability. Each plot had an area of ​​3m × 5m = 15m². Barley was planted around each plot as a protected area.

[0032] Table 1. Experimental treatments and seeding rates

[0033] The seeding rate was calculated based on the thousand-grain weight and germination rate. Barley had a thousand-grain weight of 45.0g and a germination rate of 95%, while Vitex aegypti had a thousand-grain weight of 25.0g and a germination rate of 90%. In the mixed-sowing treatments, the seed usage was proportionally converted from the monoculture seeding rate: in the 1:1 treatment, barley and Vitex aegypti each used 50% of their monoculture seeding rate; in the 2:1 treatment, barley used 67% of its monoculture seeding rate, and Vitex aegypti used 33%; in the 1:2 treatment, barley used 33% of its monoculture seeding rate, and Vitex aegypti used 67%.

[0034] Intercropping: The amount of barley and pea seeds used should be calculated based on the amount of seeds sown in a ratio of 1:1 (J1), 2:1 (J2), and 1:2 (J3) according to the amount of seeds sown in a single crop. Sow them alternately in a planting pattern of 1 row of barley and 1 row of pea. There is no limit to the plant spacing when sowing. Sow evenly as long as the plants are planted.

[0035] Mixed planting in the same row: The amount of barley and pea seeds used should be calculated based on the single crop planting amount at a ratio of 1:1 (T1), 2:1 (T2), and 1:2 (T3). Mix the barley and pea seeds evenly and sow them in the same row. There is no limit to the plant spacing when sowing. Just mix the two kinds of seeds and sow them.

[0036] 2. Field planting (1) Seed pretreatment Barley: Select seeds from barley varieties with growth characteristics of 80-120cm plant height, 3-5mm stem thickness, and 4-10 tillers to ensure the highest fresh weight and dry matter yield.

[0037] Widespread wild pea: Select varieties with growth characteristics of climbing height of 80-120cm, 10-20 branches, lush leaves, and well-developed root system (the peak flowering period is in late April, and the pod-setting period is in mid-May. The materials used in this experiment were seeds collected in the wild in Nanjing area and harvested after one year of field planting).

[0038] Before sowing, seeds can be dried for 2-3 days to improve germination rate. Before sowing, seeds should be carefully selected and treated with appropriate pesticides (mainly to control underground pests). Specific steps are as follows: Take personal protective measures. When operating, be sure to wear protective clothing, masks and rubber gloves, and carry out the operation in a well-ventilated place.

[0039] Mix 1-2 kg of 3%-5% phorate granules per acre with fine soil and seeds, then sow in rows in prepared furrows. Phoxate decomposes easily in light, so the seed treatment process should be carried out under dark conditions, and the seeds should be covered as soon as possible after sowing.

[0040] (2) Land management and sowing Land preparation requirements: Deep plowing and fine harrowing to achieve the standards of "evenness, flatness, looseness, breakage, cleanliness, and moisture"; Sowing machinery: Use precision strip seeders to ensure consistent sowing depth; Row spacing control: Strictly maintain a row spacing of 30cm; Sowing depth control: Ensure a sowing depth of 4cm to ensure uniform emergence.

[0041] In the Nanjing area, sowing typically takes place from early October to mid-November to ensure that the seeds can germinate successfully before winter and safely overwinter. Both crops are sown simultaneously to ensure synchronized growth cycles.

[0042] During the sowing process, the sowing rate and depth should be checked regularly to ensure that all management practices are consistent across different treatments except for the sowing method. The sowing rate is determined based on the thousand-grain weight and germination rate. For monoculture, the sowing rate for barley is 180 kg / hm², and for peas it is 45 kg / hm². The sowing depth is 4 cm, and the row spacing is 30 cm.

[0043] (3) Field management Water management: Use micro-sprinkler irrigation after sowing, and keep the soil moist before emergence to promote germination. Pay special attention to the fact that Vicia sativa is intolerant of waterlogging; avoid waterlogging in the field.

[0044] Other management: Throughout the entire growing season, the management measures for fertilization, irrigation and pest and disease control in each area should remain consistent.

[0045] 3. Effects of different treatments on crop growth performance 3.1 Effects of different treatments on plant height and dry matter content of barley and Vitex negundo The harvest period was based on the waxy ripening stage of barley (at which time the widely distributed wild peas were in the pod-setting stage). The fresh grass yield of each plot (3m × 5m) was measured. After measuring the plant height, 1kg of fresh grass was taken, and the grass and peas were separated and placed in an oven at 105℃ for 30 minutes to kill the greens. Afterward, it was dried at 65℃ until constant weight, and then weighed again. The dry matter content was calculated. Dry matter content % = (Weight of dried grass sample / Weight of fresh grass) × 100%. The dry matter yield per unit area was calculated based on the dry matter content. The results are shown in Table 2.

[0046] Table 2. Plant height and dry matter content of barley and vitex under different treatments.

[0047] Note: Different letters after the data in the same row indicate that the differences between treatments are significant at the P<0.05 level, and the same applies below.

[0048] Table 2 shows that barley monoculture D1 had the highest dry matter content (38.69%), while intercropping treatments generally showed a decrease. Among them, barley J3 treatment had the lowest dry matter content (36.05%), a decrease of 7.23% compared to D1, while J1 treatment maintained the highest level (38.47%), with no significant difference from monoculture. The dry matter content of widely distributed vitex was significantly higher in all intercropping treatments than in monoculture D2 (24.36%), with J1 treatment having the highest (25.81%).

[0049] The tallest barley plant was observed in monoculture (D1) (95.18 cm). Intercropping treatments showed a decreasing trend, with row-planting resulting in a greater decrease than inter-row planting. Treatment T3 had the lowest plant height (82.60 cm), a 13.22% reduction compared to D1. Intercropping significantly increased the height of pea plants, ranging from 19.60 to 25.08 cm. Treatments J3 and T3 showed the highest heights (81.02 cm), a 44.83% increase compared to monoculture.

[0050] 3.2 Effects of different treatments on the bioyield of barley and pea pods Biomass yield of barley and vitex under different intercropping treatments was determined using a diagonal sampling method: three sampling points were set at equal intervals along the diagonal of each plot. All plants (including fallen leaves) within the quadrat were cut at ground level and placed in sample bags. Barley, vitex, and weeds (if any) were completely separated, and their fresh weight was measured. The process was quick to minimize the impact of moisture loss on the fresh weight data. Blanching: The samples were placed in mesh bags and dried in a 105℃ oven for 30 minutes to quickly terminate enzyme activity and prevent respiration from consuming dry matter. Drying: The temperature was adjusted to 65℃, and drying was carried out continuously for approximately 48 hours. Weighing was performed every 2 hours until the difference between two consecutive weight measurements did not exceed 0.5% (i.e., constant weight was achieved). The dry matter content was calculated based on the fresh weight and dry matter content. The plot dry matter yield was calculated based on the fresh weight yield and dry matter content. The results are shown in Table 3.

[0051] Table 3 Fresh weight and dry weight yield of barley and vitex under different treatments

[0052] (1) Fresh weight yield analysis The highest barley fresh weight yield was observed in the T2 (parallel planting, rice:legum = 2:1) treatment (41,020.50 kg / hm²), equivalent to 79.1% of that in monoculture (D1). In the J3 and T3 treatments, which had a high proportion of legumes, the barley fresh weight yield decreased significantly to approximately 26,000 kg / hm², only 50.2%-50.5% of that in monoculture.

[0053] The fresh weight yield of Vicia sativa peaked in the T3 (parallel planting, grass:vicia = 1:2) treatment (34850.78 kg / hm²), equivalent to 79.8% of that in monoculture (D2). In the T1 (parallel planting 1:1) and T2 (parallel planting 2:1) treatments, even with barley having a density advantage, Vicia sativa still maintained a high fresh weight yield (31349.00-33517.99 kg / hm²).

[0054] The total fresh weight yield of the system showed significant differences in configuration. The T2 treatment had the highest total fresh weight yield (72369.50 kg / hm²), which was 39.5% higher than that of barley monoculture and 65.6% higher than that of pea monoculture. The total fresh weight yield of all row-mixed treatments (T1, T2, T3) was significantly higher than that of inter-row mixed treatment.

[0055] (2) Dry weight yield analysis Dry weight yield better reflects the accumulation of essential substances in plants, and its variation pattern differs significantly from that of fresh weight. The trend of barley dry weight yield was largely consistent with that of fresh weight, with the T2 treatment maintaining the highest level (15273.75 kg / hm²), equivalent to 76.1% of its monoculture yield. Dry matter content calculations showed that barley's dry matter content was generally lower in intercropping than in monoculture. Vitex dry weight yield exhibited different configuration responses, reaching its highest level in the T3 treatment (8664.39 kg / hm²), equivalent to 81.4% of its monoculture yield. Compared to fresh weight yield, vitex dry weight yield was relatively low in the J1 (1:1 intercropping) treatment (6885.27 kg / hm²), with a dry matter content of only 25.8%, significantly lower than other treatments. The total system dry weight yield remained highest in the T2 treatment (23167.52 kg / hm²), significantly higher than that of monoculture. The J2 (interval 2:1) treatment had the second-highest dry weight yield (19968.26 kg / hm²), comparable to barley monoculture.

[0056] 3.3 Effects of different treatments on crude protein production The crude protein content in harvested barley and wild pea was determined using a protein analyzer (KJEITEC2300, Foss, Denmark), and the crude protein yield was calculated as follows: crude protein yield = dry matter yield per unit area × crude protein content % × 100%. The results are shown in Table 4.

[0057] Table 4. Effects of different treatments on crude protein content and yield of soybean.

[0058] Table 4 shows that the crude protein content exhibited a significant species-specific response among the treatments. Barley showed the highest crude protein content in monoculture D1 (11.46%), which generally decreased in intercropping treatments, with the lowest being in treatment T1 (8.36%). In treatments J2 and J3, barley crude protein content remained at a high level (10.34-10.59%), indicating that intercropping was beneficial in maintaining barley protein quality. Vitex trifolia showed the highest crude protein content in monoculture D2 (19.45%), while in intercropping treatments, treatments J1 (18.89%) and T2 (18.70%) maintained high levels. With increasing proportions of Vitex trifolia in mixed plantings (J3, T3), its crude protein content showed a decreasing trend.

[0059] Crude protein yield reflects the actual protein production capacity of the system. Barley treatments T2 and J2 yielded crude protein of 1444 kg / hm² and 1407 kg / hm², respectively, equivalent to over 60% of monoculture yield, indicating that barley can maintain a high contribution to protein production at a 2:1 ratio. Vitex treatments T1, T2, and T3 showed high crude protein yields (1475-1542 kg / hm²), reaching over 70% of monoculture yields. In contrast, intercropping treatments of vitex yielded lower protein (1151-1313 kg / hm²). Treatment T2 (intercropping, grass:vitamin = 2:1) performed best, reaching 2920.29 kg / hm², 27.1% higher than barley monoculture and 41.1% higher than vitex monoculture. Treatment J2 (intercropping, grass:vitamin = 2:1) was second best, with a total yield of 2558.94 kg / hm².

[0060] The protein production efficiency of the system was further evaluated by calculating the protein-to-land-equity ratio. The land-equity ratio = (Yib / Ymb) + (Yiv / Ymv), where Yib and Yiv are the crude protein yields of intercropped barley and pea, respectively, and Ymb and Ymv are the crude protein yields of the corresponding monocultures.

[0061] The land equivalent ratio of treatment T2 reached 1.41 (barley 0.63 + pea 0.78), demonstrating a significant advantage in protein production. Treatment J2 had a land equivalent ratio of 1.24 (barley 0.61 + pea 0.63), also showing a good advantage in protein production. All mixed-sowing treatments had a land equivalent ratio greater than 1.0.

[0062] 3.4 Effects of different treatments on the content of neutral detergent fibers, acid detergent fibers, and hemicellulose The Van der Waals method was used to determine the content of neutral detergent fiber and acid detergent fiber. Hemicellulose content = neutral detergent fiber content - acid detergent fiber content. The results are shown in Table 5.

[0063] Table 5. Effects of different treatments on the content of neutral detergent fiber, acid detergent fiber, and hemicellulose.

[0064] Table 5 shows that in most intercropping treatments, the neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents of barley tended to be lower than or close to those of monoculture (D1). The J1 treatment (1:1 intercropping) had the lowest NDF and ADF contents among all treatments (53.51%, 33.23%). The NDF and ADF contents of Vitex negundo remained relatively stable across all intercropping treatments compared to monoculture (D2). The changes in hemicellulose content in barley and Vitex negundo were similar to those in NDF and ADF content.

[0065] 3.5 Effects of different treatments on soil physicochemical properties Before sowing and after harvest, soil samples from the 0-20cm soil layer were collected using the "S" shaped sampling method. The samples were mixed, air-dried, ground, and sieved before testing.

[0066] According to the "Methods for Soil Agricultural Chemical Analysis", the nutrient components and element contents in the soil were determined. Specifically, pH was measured using a pH meter; organic matter content was determined by FeSO4 titration after K₂Cr₂O₇-H₂SO₄ digestion; total nitrogen content was determined using the Kjeldahl method; total phosphorus was determined using the molybdenum-antimony colorimetric method described in "HJ 632-2011 Determination of Total Phosphorus in Soils - Alkali Fusion-Molybdenum-Antimony Spectrophotometric Method"; total potassium was determined using the flame photometer method described in "LY / T 1234-2015 Determination of Potassium in Forest Soils"; alkaline-available nitrogen content was determined using the alkaline diffusion method; available phosphorus content was determined using the ammonium fluoride-hydrochloric acid solution molybdenum-antimony colorimetric method; and available potassium content was determined using ammonium acetate extraction-flame photometer. The results are shown in Table 6.

[0067] Table 6. Changes in soil physicochemical properties under different treatments

[0068] Note: CK indicates that no plants have been planted.

[0069] (1) Characteristics of soil pH variation Table 6 shows that the pH of the control group (CK) was 6.75, and the pH range of each treatment was 6.73-7.35. The T2 treatment had the highest pH (7.35), which was significantly higher than that of the CK by 0.60 units. The pH of the J2, J3, and T1 treatments was also significantly higher than that of the CK, indicating that the intercropping system had a mitigating effect on soil acidification.

[0070] (2) Dynamics of organic matter accumulation The organic matter content of the control group (CK) was 11.52 g / kg, while the organic matter content of each treatment ranged from 14.36 to 19.61 g / kg. The J2 treatment had the highest organic matter content (19.61 g / kg), which was more than 70% higher than that of the CK. The organic matter content of the T2 and J1 treatments was also significantly higher than that of the CK, with increases of 66.5% and 60.7%, respectively.

[0071] (3) Characteristics of nitrogen transformation Treatment T2 had the highest total nitrogen content (1.47 g / kg), which was 54.7% higher than the control (CK). Treatment T3 had the highest available nitrogen content (133.48 mg / kg), which was 30.3% higher than the control (CK). The total nitrogen content of all treatments was higher than that of the control (CK), indicating that planting vegetation helps to accumulate nitrogen in the soil.

[0072] (4) Characteristics of phosphorus and potassium conversion Treatment T2 had the highest total phosphorus content (0.69 g / kg), a 25.5% increase compared to the control (CK). Treatment D1 had the highest available phosphorus content (25.90 mg / kg), a significant 127.6% increase compared to the CK. The fact that most treatments had higher available phosphorus content than the CK indicates that plant cultivation promoted phosphorus activation. Treatment D2 had the highest total potassium content (14.99 g / kg), a 30.0% increase compared to the CK. Treatment D1 had the highest available potassium content (131.34 mg / kg), a 31.9% increase compared to the CK.

[0073] 3.6 Effects of different treatments on interspecific competition 3.6.1 Effects of different treatments on relative yield and competition rate among species The relative yield of barley is RYg = Ygl / (pYg), and the relative yield of peas is RYl = Ylg / (qY1). Where Ygl is the yield per unit area of ​​grasses in mixed planting (kg / hm²). 2 Yg is the yield per unit area of ​​grasses when sown alone (kg / hm). 2 ), p is the sowing ratio of oats in the mixed planting area, and Ylg is the yield of leguminous forage grasses per unit area (kg / hm) when mixed planting. 2 Yl represents the yield per unit area of ​​leguminous forage grasses when sown alone (kg / hm). 2 ), q is the sowing ratio of leguminous forage grasses in the mixed planting area.

[0074] Interspecific competitiveness refers to the ability of a species population to compete in a mixed-species community, calculated using the following formula: Competition Rate (CR). The CR calculation formula is: CRi = (Yij / Yii × Zij) / (Yji / Yjj × Zji). Where CRi is the competition rate of species i; Yii is the biomass of monoculture i (kg / hm²). 2 Yjj represents the biomass of monoculture j (kg / hm). 2Yij represents the biomass of i in the mixed cropping (kg / hm). 2 Yji represents the biomass of j in the mixed sowing (kg / hm). 2 Zij represents the sowing proportion of seed i in the mixed sowing; Zji represents the sowing proportion of seed j in the mixed sowing. Zij + Zji = 1. When calculating the competition rate, biomass is the dry matter yield per unit area (kg / hm²). 2 The results are shown in Table 7.

[0075] Table 7. Relative yield and competition rate of barley and pea under different treatments.

[0076] Table 7 shows that barley and pea pods exhibit general intercropping advantages and interspecific promoting effects in terms of relative yield and competition rate, as specifically demonstrated below: (1) Analysis of relative output pattern The relative yield of barley peaked at 1.40 in the T3 (row-to-row, grass:legad = 1:2) treatment, indicating a 40% increase in barley plant productivity compared to monoculture. The J3 (interrow-to-row, grass:legad = 1:2) treatment also performed well (1.36). In contrast, the relative yields of barley in the J2 and T2 treatments were close to or below 1.0, indicating suppressed individual development under density advantage. The relative yield of vitex showed a different response pattern. It reached 2.23 in the T2 (row-to-row, grass:legad = 2:1) treatment, indicating a 123% increase in vitex plant productivity compared to monoculture. The J2 (interrow-to-row, grass:legad = 2:1) treatment also performed excellently (1.80). The sum of the relative yields of the two crops in all intercropping treatments was greater than 2.0, with the T2 treatment reaching 3.34 and the J2 treatment reaching 2.75.

[0077] (2) Analysis of competition rate and interspecific relationships The competition rate of barley was greater than 1.0 in treatments J3 and T3 (1.12 and 1.02), indicating that barley's competitive ability was enhanced when it was at a density disadvantage. Conversely, in treatments J2 and T2, the competition rate of barley was only 0.46, indicating that its competitive ability was relatively weakened under a density advantage. The competition rate of vitex showed the opposite trend. It reached its highest level in treatments J2 and T2 (2.15 and 2.19), showing extremely strong competition under a density disadvantage. In treatment J3, the competition rate was the lowest (0.89), indicating relatively weak competitive ability under a density advantage. The ratio of competition rates shows that in treatments J2 and T2, the competition rate of vitex was 4.7-4.8 times that of barley, indicating that vitex held an absolute competitive advantage in these treatments. In treatments J3 and T3, the competition rate was close to 1.0, indicating a relatively balanced competitive state between the two crops.

[0078] (3) The interaction effect between configuration mode and mixing ratio Configuration pattern effect: Intercropping in the same row was more advantageous in promoting the relative yield of Vitex acuminata, especially in the T2 treatment where the relative yield of Vitex acuminata reached 2.23. Intercropping in barley showed less variation in relative yield across treatments.

[0079] Intercropping ratio effect: A 2:1 ratio is most conducive to stimulating the individual potential of widespread wild vetch (relative yield 1.80-2.23), while a 1:2 ratio is most conducive to the individual development of barley (relative yield 1.36-1.40). The development of the two crops is relatively balanced at a 1:1 ratio.

[0080] 3.6.2 Impact of different treatments on land use efficiency Land Equivalent Ratio (LER) = (Yib / Ymb) + (Yiv / Ymv), where Yib and Yiv are the yields (kg / hm) of intercropped barley and wild pea, respectively. 2 Ymb and Ymv are the corresponding single-crop yields (kg / hm). 2 ).

[0081] Table 8 Land Equivalent Ratio under Different Treatments

[0082] Note: Different letters after the data in the same column indicate significant differences between treatments at the P<0.05 level. Intercropping dominance classification: land equivalent ratio 1.00-1.20 is medium, 1.21-1.40 is good, and >1.40 is excellent. Land saving rate = (1-1 / land equivalent ratio)×100%.

[0083] Table 8 shows that all intercropping treatments exhibited significant intercropping advantages (land equivalent ratio > 1), indicating the universality of the rice-legum intercropping system in improving land use efficiency. The land equivalent ratios of the various intercropping treatments ranged from 1.17 to 1.48, with an average land equivalent ratio of 1.27. The intercropping system saved 21.3% of the land area compared to the monoculture system, meaning that the same yield could be obtained. The average land equivalent ratio of the row intercropping treatment (1.36) was significantly higher than that of the inter-row intercropping (1.19), indicating that row intercropping was more advantageous in improving land utilization. Under the row intercropping pattern, the 2:1 ratio (T2) had the highest land equivalent ratio (1.48), followed by the 1:1 ratio (T1, 1.32) and the 1:2 ratio (T3, 1.28). A moderate barley density advantage was beneficial for maximizing land utilization.

[0084] 3.7 Correlation Analysis 3.7.1 Correlation analysis between soil fertility and crude protein yield Calculate the Pearson correlation coefficient (r) and use hypothesis testing to determine whether it is significant.

[0085] Table 9. Correlation between soil fertility indicators and total crude protein yield in the system

[0086] Table 9 shows that there is a significant positive correlation between total nitrogen content and total crude protein yield in barley; and a highly significant positive correlation between total nitrogen content and total crude protein yield in widely distributed wild pea, indicating that for every unit increase in soil total nitrogen, total protein yield and legume protein yield will increase with a very high probability and magnitude. Organic matter is significantly positively correlated with all crude protein yield indicators. Alkali-available nitrogen is significantly positively correlated with total crude protein yield and barley crude protein yield, indicating the dependence of gramineous crops on soil available nitrogen.

[0087] In summary, compared to conventional planting techniques (monocropping), in terms of land utilization, the method provided by this invention can increase the land equivalent ratio to 1.48 and the land saving rate to 32.4%. That is, this invention enhances land-saving potential, saving nearly one-third of land resources for the same yield, while conventional intercropping techniques can only achieve a land equivalent ratio >1, increasing the land saving rate by 10-20%. Regarding protein production, conventional intercropping techniques only focus on total yield, neglecting quality and efficiency, while this invention can increase the total crude protein yield by up to 27.1%, achieving amino acid complementarity between cereals and legumes, efficient protein production, and improved forage nutritional value. Regarding soil organic matter content, conventional planting techniques (monocropping) can only maintain or cause a slow decline in soil organic matter content, while this invention can... The organic matter content of the soil in the planting area increased by 66.5% compared to the blank area, transforming the crop production system from a "carbon source" to a "carbon sink" and significantly improving the basic soil fertility. Regarding soil nitrogen reserves, conventional planting methods rely on chemical fertilizer input, which carries the risk of loss. However, this invention increases the total nitrogen content by 54.7% through biological nitrogen fixation, significantly reducing dependence on chemical nitrogen fertilizers and constructing a sustainable nitrogen cycle. In terms of soil acidification improvement, conventional planting methods generally suffer from acidification. This invention can significantly increase the soil pH value and effectively improve acidification. That is, the planting method provided by this invention can transform soil nutrients from "passive consumption" to "active enrichment," forming a new model of "producing while nourishing the soil." This provides a low-cost, bio-based alternative for soil acidification improvement, which can reduce dependence on lime.

[0088] As can be seen from the above embodiments, the present invention provides a method for intercropping barley and pea, which can improve soil fertility, improve soil acidification, achieve sustainable nitrogen cycle, increase the yield and quality of barley and pea, and improve land utilization.

[0089] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for intercropping barley and widespread wild pea, characterized in that, Includes the following steps: (1) Dry the seeds of barley and wild pea for 2-3 days, then mix them with water to obtain pretreated seeds; (2) Sow the pretreated seeds in the pretreated land in the form of mixed planting in the same row or between rows, manage the field, harvest, and obtain barley and peas. The mixing ratio of barley and broad-based wild vetch in the same row is 100-140 kg / hm². 2 10-20 kg / hm 2 .

2. The method according to claim 1, characterized in that, In step (1), the barley is characterized by a plant height of 80-120cm, a stem thickness of 3-5mm, and 4-10 tillers; the widely distributed wild pea is characterized by a climbing height of 80-120cm and 10-20 branches.

3. The method according to claim 1, characterized in that, In step (1), the drying method is natural drying; the agent used in the seed dressing is phorate, and the effective concentration of phorate is 3%-5%.

4. The method according to claim 1, characterized in that, In step (1), the application rate of phorate is 1.5-2.5 kg / mu.

5. The method according to claim 3 or 4, characterized in that, In step (1), the seed mixing process also includes fine soil, and the amount of fine soil added is 1-2 kg / mu.

6. The method according to claim 1, characterized in that, In step (1), the seed mixing is carried out in the dark.

7. The method according to claim 1, characterized in that, In step (2), the mixing ratio of barley and wild pea during intercropping is 80-100 kg / hm. 2 20-25 kg / hm 2 .

8. The method according to claim 1, characterized in that, In step (2), the sowing method is row sowing, the sowing depth is 3-5cm, and the row spacing is 28-32cm.

9. The method according to claim 1, characterized in that, In step (2), the sowing time is from early October to mid-November, and barley and wild pea are sown at the same time; the pretreated land meets the standards of "even, flat, loose, broken, clean and moist".

10. The method according to claim 1, characterized in that, In step (2), the field management includes water and fertilizer management and pest and disease control; the harvest period is the barley wax ripening period.

Images