Method for replacing and controlling guayule with tall fescue

[0032] Example 1 Competitive experiment of tall fescue and guayule

[0033] The experiment was conducted in the network room of the Institute of Plant Protection, Shandong Academy of Agricultural Sciences. The alternative plant species is tall fescue and the competition object is guayule. The diameter of the upper mouth of the tested flowerpot is 25 cm, and the height is 20 inches. The soil is top soil of farmland, which is alkaline loam soil, and the organic matter content is 30.9g/Kg. Sow on April 5, 2013. The replacement plant tall fescue is 300 kg/ha in accordance with the recommended planting density, the sowing depth is 1 cm, and the guayule set 0, 2, 4, 8, 16, 32, 64 plants/pot, covered with soil 1-2 mm, appropriate amount of multi-sown when sowing, wait until the five-leaf stage of guayule is fixed to the number of plants. No fertilizer was applied throughout the growth period of the test plants. On August 15, 2013, the aboveground parts of each processed guayule and tall fescue were respectively cut, and the fresh weight was weighed, dried in an oven to a constant weight, and the dry weight was weighed; the results are shown in Table 1.

[0034] Table 1 Comparison of the competitiveness of tall fescue against guayule

[0035] .

[0036] In terms of the percentage of tall fescue to the total amount of mixed species, the competition intensity of tall fescue against guayule can be seen. The higher the percentage, the stronger the competitiveness of alternative plants. The test results show that when the number of guayule plants is small, tall fescue can completely compete with guayule through interspecific competition. When there are 2, 4, 8, 16 guayule plants in each pot, tall fescue can almost Make guayule all dead; when the density of guayule is higher, tall fescue is also very competitive. When guayule has 32 and 64 plants per pot, the percentage of fresh weight of tall fescue can reach 81.0 respectively. %, 67.6%, and the percentage of dry weight reached 86.3% and 80.4% respectively. Therefore, the results show that tall fescue is a good plant material to compete for guayule, and it can be a substitute for controlling guayule.

[0037] Example 2 Field trial of tall fescue control of guayule (April)

[0038] The experiment was conducted in Shizilu Town, Junan County, Shandong Province.

[0039] The test site is an abandoned yard with flat terrain and no crops. The annual density of guayule is very high. A large number of dry guayule plants were distributed on the ground before site preparation, and some guayule seedlings began to be unearthed. The density of guayule seedlings unearthed by visual inspection is very high, which can reach 100 plants/㎡. The planting time is April 24, 2014. Firstly, cut off the dry guayule plants of the previous year, and sown tall fescue after shallow rotation. The sown rate is 300 kg/ha; the thickness of the cover soil is 1-3 cm after sowing. When tall fescue grows to 20 cm, use herbicide to eliminate broad-leaved weeds once (the herbicide used is tribenuron-methyl or 2-methyl-4-chloropyridine, the dosage is the conventional dosage). When tall fescue grows to about 20 cm, cut; in summer, cut once a week, with a stubble height of 5-6 cm; in autumn, cut once every 3-4 weeks with a stubble height of 5-6 cm. Use thiophanate-methyl, carbendazim, or Tetrimide to prevent and control diseases such as brown spot, rust and powdery mildew; use phoxim and deltamethrin to control grass borers, mole crickets, scarabs and other pests. On August 10, 2014, the plant height, number of plants and fresh weight of the whole plant per square meter of guayule in the replacement area of ​​tall fescue and the control area were investigated and recorded. The fresh weight was used to calculate the control effect; the results are shown in Table 2. .

[0040] Table 2 The effect of tall fescue in preventing and controlling guayule (2014.8, Junan, Shandong)

[0041] .

[0042] The test results showed that tall fescue grew rapidly after emergence, and the speed was significantly faster than the guayule unearthed in the same period. Planting the replacement plant tall fescue in the wasteland of guayule invasion has a good prevention and control effect on guayule, and the prevention and control effect reached 91.0% (Table 2). Therefore, the use of tall fescue as an alternative to control guayule at the emergence of guayule has the advantage of good control of guayule.

[0043] Example 3 Field trial of tall fescue control of guayule (June)

[0044] The trial was conducted in Junan County, Shandong Province on June 12, 2014.

[0045] The test site is an abandoned yard, the terrain is flat, no crops are planted, and the annual density of guayule is very high. Before site preparation, a large number of guayule grows vigorously on the ground, the plant height is 20-60 cm, and the visual inspection can reach 100 plants/㎡. The sowing time of tall fescue is June 12, 2014. First pull out the unearthed guayule plants and last year's dried plants, and sown after shallow rotation. The sown amount is 300 kg/ha; the thickness of the cover soil after sowing is 1-3 cm. When tall fescue grows to 20 cm, the herbicide is used for weeding once (the herbicide used and the amount are the same as in Example 2). Cut tall fescue whenever the height of the tall fescue grows to 20 cm; in summer, it grows fast, cut every other week, and the stubble height is 5-6 cm; in autumn, cut once every 3-4 weeks, and the stubble height is 5 -6 cm (the cutting operation is the same as in Example 2). On October 10, 2014, the plant height, number of plants and the fresh weight of the whole plant per square meter of guayule in the replacement area of ​​tall fescue and the control area were surveyed and recorded. The fresh weight was used to calculate the control effect; the results are shown in Table 3.

[0046] Table 3 The effect of tall fescue in preventing and controlling guayule (2014.10, Junan, Shandong)

[0047] .

[0048] The test results showed that the effect of planting in June instead of controlling guayule was slightly worse. At this time, the temperature was high and the growth rate of guayule after unearthed was faster than that in April and May, and the control effect of tall fescue was relatively poor. In October of that year At the time of the investigation, the control effect reached 68.8%, which was lower than the 91.0% of the alternative control in April.