Study On Effect Of Chemical Emasculation And Heterosis Of Different Hybrids In Common Buckwheat

Buckwheat has important economic value in China,and has high development value and utilization value in feed and medicine.Chemical emasculation technology has the advantages of simple operation,wide source of parents,no cytoplasmic adverse effect,free mating,stable male sterility and so on.It has become an effective way to use heterosis,and an effective way to overcome the difficulty of hand-emasculation.At present,chemical hybridizing agent have been widely used in the study of male sterility in wheat,rape,rice,cotton and other crops,but the application of chemical hybridizing agent in buckwheat male sterility is rarely reported.Therefore,it is necessary to carry out the screening study of chemical hybridizing agent and the study of effect of Chemical Emasculation in common buckwheat,which is of great significance for the configuration of excellent common buckwheat hybrids,the improvement of common buckwheat yield and the improvement of common buckwheat traits.In this experiment,chemical agents were used to treat common buckwheat materials,and the effects of chemical hybridizing agent on plant morphology,growth and agronomic traits were studied.The male sterility effect of chemical hybridizing agent and its influence on pollen vitality and pistil vitality were studied,so as to clarify the male sterility mechanism of chemical hybridizing agent on common buckwheat,select good chemical hybridizing agents,and explore the chemical emasculation method of common buckwheat.At the same time,three common buckwheat hybrids were bred by using four parents and two collocation methods.The growth traits,heterosis and yield of different hybrids were analyzed.,which provided a theoretical basis for chemical emasculation and heterosis utilization of common buckwheat.The main conclusions are as follows:(1)Screening of chemical hybridizing agents: Five kinds of chemical maleicides were selected.After treatment,the effects of the drugs on the growth and development of common buckwheat,as well as the phytotoxicity,morphological and agronomic traits,and the male sterility effect were studied.The halosulfuron-methyl were screened.(2)The male sterility effect of halosulfuron-methyl and its influence on the growth and development of common buckwheat: Under the same concentration of halosulfuron-methyl,the more times of drug treatment,the higher proportion of sterile plants,the lower proportion of fertile plants,the lower seed setting rate,and the better male sterility effect;under the same treatment times,within the designed concentration range,the higher the concentration,the higher proportion of sterile plant,the lower proportion of fertile plants and seed setting rate,and the better male sterility effect.At 1.3% dilution concentration,3 times of drug treatment had the best effect on the male sterility of plants,and the seed setting rate in the isolation area was the lowest,5.31 %,which was 18.26% lower than that of the control(23.57%).The morphological effect and phytotoxicity of the plant were slight,but the initial flowering period was delayed by 9 days,and the growth days were prolonged by 13 days.It had a certain role in promoting agronomic traits such as number of main stem section,number of branches and flower clusters per plant.Studies have shown that the ideal male sterility effect is basically achieved.(3)Male sterility mechanism of halosulfuron-methyl: Scanning electron microscope observation showed that after halosulfuron-methyl treatment,the content of pollen grains decreased,the staining was shallow,the shape of pollen grains was not full,shrinkage and shriveled,and the number of normal pollen decreased,affecting pollen viability.The pistil morphology did not change under drug treatment,the style was round and full,and there was no difference with the control.(4)The effect of halosulfuron-methyl on pistil activity: Under halosulfuron-methyl treatment,the seed setting rate was 91.49% by artificial pollination.The seed setting rate of spraying plants under natural pollination was about 32%,and there was no difference between the two methods and the control.Therefore,the drug treatment had no effect on the vitality of pistil stigma.(5)The heterosis of different common buckwheat hybrids: When the parents’ growth traits were not significantly different,the growth traits of the three hybrids were basically the same with their parents;In terms of economic traits,the advantages of different combinations and different hybrids are different,mainly in the average advantage;In terms of yield,different combinations showed different advantages.Combination 1(P1 and P3,Pingqiao 8 and Xinong T1106)was a strong combination.The heterosis of different hybrids was different.The heterosis of equal quality bulk crosses was the strongest,followed by orthogonal hybrids.The yield traits are mainly manifested in the superstandard advantage.