Effects Of Herbicides On Pea Growth And Evaluation Of Field Control

Peas are widely used,mainly for food and vegetables,and can also be used for forage and green manure,it is one of the important small grain crops in China.The problem of weed damage has seriously hindered the promotion of pea planting,herbicides have become an important technical measure to control weeds in farmland,however,there are currently no efficient and safe herbicides for weeds in pea fields.For this reason,this study took the‘Xiwan-2’as the test material,totally used 11 herbicides,among them,6 kinds of pre-emergence herbicides were used,5 kinds of post emergence herbicides were used,and set clear water contrast(CK1),artificial weeding(CK2),the screening of herbicide types and dose test is carried out.Field experiments were conducted to investigate weed species,study the effects of different herbicides on weeds control,discuss the effects of various herbicides on growth process,morphological characteristics and economic benefits,designed to screen efficient and safe herbicides for pea fields,in order to provide technical basis for the construction of weed control system for peas.The research conclusions as follows:(1)There are 13 species of weeds in 7 families in pea fields in Guanzhong region of Shaanxi,9 species are broad-leaved weeds,accounting for 69.23%,is the main weed type.Different kinds of herbicides have different degrees of control effects on the number of weeds and fresh weight,and the control effect of the number of weeds is positively correlated with the control effect of fresh weight.The best comprehensive control effect is50%acetochlor and 33%pendimethalin before seedling,and 10%quizalofop-p and12%clethodim after seedling.(2)Different kinds of herbicides have different effects on the growth and development of peas.From overwintering to flowering stage,herbicide treatments had significant effects on plant height and relative chlorophyll content of pea,but the effect was not significant from the beginning of pod stage.The accumulation of dry matter in root,stem and leaf organs of pea was inhibited to varying degrees by all treatments,the removal rate and translocation rate of dry matter in stem and leaf organs of all treatments were higher than that of artificial weeding,and the removal rate and translocation rate of dry matter in leaf organs were higher than that in stem organs.(3)Different kinds of herbicides have significant effects on yield,compared with artificial weeding,except for 10.8%haloxyfop-r-methyl,the yield of the other herbicides showed a certain increase,among them,50%acetochlor,33%pendimethalin,50%napropamide,and 12%clethodim could increase the yield of autumn pea by more than20%.The net income of all herbicide treatments increased,and the net income of33%pendimethalin and 12%clethodim treatments was the highest among herbicides in the same period.(4)The results of investigation on weed species in pea fields in northern region region of Shaanxi showed that there were 12 species in 7 families,broadleaf weeds accounted for 8species,accounting for 66.67%of the species.broad-leaved weeds were the dominant weeds.Different doses of herbicides have different degrees of control effects on the number of weeds and fresh weight,and the control effect of the number of weeds is positively correlated with the control effect of fresh weight.the best comprehensive control effect of33%pendimethalin before seedling at 5625 ml/hm~2 and 12%clethodim after seedling at 675ml/hm~2.(5)Different doses of herbicides have certain effects on the growth and development of peas.In the early growth stage of pea,the inhibition of plant height and relative chlorophyll content is greater,however,with the advance of growth period,the influence on the growth and development of pea gradually decreases.The inhibitory effect of 33%pendimethalin at5625 ml/hm~2 and 12%clethodim at 675 ml/hm~2 on plant height and chlorophyll content of pea was the largest and longest in the same period.(6)Except 50%acetochlor and 12%clethodim of 675 ml/hm~2,the others doses of herbicides yield was higher than that of the artificial weeding,and the yield increase of herbicide treatment after seedling was significantly higher than that of pre-seedling herbicide.33%pendimethalin of the pre-seedling herbicide at 2250 ml/hm~2 and 12%clethodim of the post-seedling herbicide at 450 ml/hm~2 have higher yield than other herbicides at the same time,the yield increased by 17.46%and 31.75%compared with artificial weeding.(7)Net income from different doses of herbicide treatment was higher than artificial weeding,the net income of pre-seedling herbicide was the highest at 2250 ml/hm~2 of33%pendimethalin,which was 6025.50 yuan/hm~2,and increased income by 65.27 times.The net income of post-seedling herbicide was the highest at 450 ml/hm~2 of 12%clethodim,which was 7009.50 yuan/hm~2,and increased income by 75.77 times,which was the highest in all herbicide treatments.In summary,combined with the control effect,safety and economic benefits of herbicides,this experiment recommended that pea growers in Guanzhong and northern area of Shaanxi,spray 33%pendimethalin before seedling at 2250 ml/hm~2 or 12%clethodim after seedling at 450 ml/hm~2.