| Rice, as one of the three major food crops, is the main grain ration of the whole country, and also the main source of the income of the farmers. With the introduction of the policy of land circulation and national agricultural projects to support efforts to increase for, more and more large plantations and cultivation cooperatives have emerged, then the traditional rice planting pattern will be broken to mechanization, simplization, industrialization. This experiment studied the effect of Thiamethoxam on rice seedling growth, rice thrips control and yield by two different application methods, spraying and seed dressing; at the same time, the effect of seed dressing of Thiamethoxam on the chemical and physical properties of rice, chlorophyll fluorescence parameters and root activity were studied; and by the two application methods, the effect on rice yield and economic benefits, was analysed from chemicals and artificial cost, rice yields,aims to explore a simple, economic and effective measures of pesticide application, to provide reference for a large area of rice planting application methods. The following main results are obtained.1.Through the field test, the research of 30% thiamethoxam treatment effect on rice seedling agronomic traits and yield traits, experimental results show that dingchongan seed treatment can improve the germination rate of rice seeding fields, and spray treatment almost no role; two application methods on rice root growth and adventitious root production was promoted the role, and the same dosage dressing better, but have little effect on tiller number and grain weight; two kinds of application methods, set dingchongan with a certain degree of 10g/667m2 effect on rice spikelets per panicle, but when the concentration of 20g/667m2, inhibition of ear length; spray treatment effect is better than that of seed dressing processing, and promoting effect on seed setting rate is on the contrary, when the dosage increased to 20g/667m2, two ways of panicle length and seed setting rate were promoted Weakening.2.16 days after processing, each treatment can effectively control the thrips, volume sharp rate is only 3.17%~14.53%, significantly lower than CK(52.46%). Their control effect can reach 68.2%~94.0%; After treating with different dosage(20g/667m2 10g/667m2)of Dingchongan, spray treatment of control effect was 88.8%, 94.0%, that was significantly higher than the control effect of seed treatment,it is 68.2%, 81.4%. 30 days after processing, the control effects were decreased on different amplitude, volume sharp rate rose to 14.32%~25.34%, but still lower than 58.73% of the CK group; Dingchongan spray treatment control effect was 56.9%, 66.9%, lower than 65.7%, 75.6% ofthe seed dressing treatment prevention control effect. It shows that dingchongan spray is rapidly available,the seed processing longer hold effect, however, can lengthen efficacy.3.Seed Processing Experiment showed that dingchongan and ruisheng treatment could significantly promote the leaves of rice defense enzyme system(superoxide dismutase SOD, peroxidase POD, too catalase CAT),when the administering dose is 20 g / 667m2, time for 7d and 14 d. It is beneficial to remove or mitigate the effects of posion which caused by the excessive reactive oxygen and free radical generation that produced in rice body, which could enhance disease resistance in rice, with the passage of time, the promoting effect become slowly or disappear. Rice after a given dressing process of dingchongan, MDA content decreased, and the higher the amount the greater of decline, but with the passage of time, the content of MDA increased, the inhibition degree reduced. Early treatment, dingchongan seeding made that the chlorophyll content of rice shows inhibition, and as the concentration increases, the degree of inhibition increased,after treatment 21 d, the inhibition disappears. After the seed processing of dingchongan, the maximum photochemical efficiency φPo improves with time; Dark adaptation under PSⅡreaction center open degree Ψ o no obvious difference; ABs/CSm change owing to the different processing time and concentration, the initial treatment, a low concentration group ABs/CSm value lower than the CK, with the passage of time, it rose gradually; DIo/CSm value were significantly higher, which indicates that dingchongan seed could increased heat dissipation per unit leaf area to protect the photosynthetic structure.4.After 30% thiamethoxam processing, the root activity promoting effect is obvious, the degree promotion with the increase of concentration, the first increase and then decrease. After treatment 21 d, the treated group of dingchongan was decreased, and the Root activity of the ruisheng was still increased, which showed that Rui Sheng treatment has a longer duration or it could sustained release.5.The yield investigation and economic benefit analysis, the results were as follows: Compared to dingchongan spraying and seed dressing treatments, the average income increased 32 yuan, and compare dingchongan with seed treatment with Rui sheng seed dressing treatment, income increase in the basic flat; under the same dose treatment, compare seed treatment with spraying income, the increase is the main application labor cost savings, as well as the increase of rice paddy, including the cost of labor per mu save 12 yuan, income of output increased 20, 27.5 yuan; Although CK group was less cost, but the yield income far less than the fungicides and spray processing.Comprehensive above, it can be seen that the main reason for the rice yield is the seed dressing treatment increased the rice seed setting rate and root activity. Compared with spray treatment, seed dressing treatments can reduce the amount of labor input,and save the labor cost and increase the yield of rice; It is similar to using dingchongan or rui sheng seed on rice growth effect and thrips control effect, as well as create economic benefits was essentially flat; Therefore dingchongan seed can be used in direct seeding paddy rice production replacing ruisheng.It recommended dose for 2.22-4.44g/kg. |
PDF Full Text Request