Research And Development Of Menghai Fragrant Rice Seedling Raising Technology And Field Verification

With the development of industrialized rice seedling raising technology and mechanized rice seedling transplanting technology,the existing seedling raising technology has been difficult to meet the quality requirements of mechanically transplanted rice seedlings.At present,there are a wide variety of traditional nursery nutrient soil and organic-inorganic material mixed nursery substrate in the market,and there are still some urgent problems to be solved,such as high cost,uneven fertilizer efficiency and damage to the ecological environment.Menghai county has a cultivated area of about 44700 hectares and a rice planting area of about 23900 hectares.It is rich in conventional high-quality rice such as diantun 502 and Yunjing 37,and has a certain scale and brand effect.However,the traditional way of cultivating seedlings in Menghai has some problems,such as poor seedling quality and frequent rice blast.Selecting several common commercial seedling raising substrates in Menghai rice area,mixing soil and adding seedling strengthening agent to the commercial seedling raising substrates,to ensure the stable supply of effective nutrients in the substrates,can effectively improve these problems.Therefore,diantun 502 was used as the test rice,through the greenhouse seedling raising experiment and field verification experiment,this study developed special soil mixing seedling raising substrate and special strengthening agent in Menghai rice area,to explore the impact of menghai xiangrice special integrated seedling raising technology on seedling quality.The effects of integrated seedling raising technology on rice field growth and development,nutrient absorption,yield and rice quality were further studied.The main results are as follows:1.The investigation results of Menghai fragrant rice seedling raising link show that there is no substrate seedling raising technology in local rice seedling raising,and the traditional red soil is still used to cultivate seedlings.The soil is sticky and lack of fertilizer.The time length of seedling raising varies greatly and is unreasonable,the period of seedling raising is long,the field management varies greatly among farmers,and there is no unified seedling raising standard.This resulted in poor quality of seedlings,uneven quality of seedlings and frequent occurrence of rice blast.However,the area of mechanical transplanting in Menghai county has reached 80%,and the existing seedling raising technology is difficult to meet the requirements of mechanical transplanting for seedling quality.The way to solve the problem of raising fragrant rice seedlings in Menghai must be worked out as soon as possible,starting from cultivating strong seedlings,improving the yield of fragrant rice at the source and controlling the yield and quality of fragrant rice.2.Under the condition of dry rice seedling raising in Menghai rice region,the seedling raising substrate has a good positive regulation effect on improving the quality of rice seedlings.Three kinds of commercial seedling raising substrates were selected: Banna Wangcang seedling raising substrate,microbial carbon fertilizer containing humic acid and tobacco stalk organic fertilizer,which were mixed with red soil in different proportions.It was found that adding seedling substrate(40% ～ 50%)to red soil could effectively improve seedling morphology,improve seedling quality,promote rice root growth and morphogenesis,and significantly increase seedling root activity and root consolidation ability.When the amount of substrate(a local commercial substrate)was 40%,the seedling index,root shoot ratio and growth function reached significant differences(P < 0.05).Under these experimental conditions,the most suitable seedling raising substrate and mixing ratio are: 40% Banna Wangcang seedling raising substrate +60% red soil(mass ratio).3.Under the field conditions after transplanting dry-raised seedlings of late rice in Menghai,adding Bannawangcang matrix seedling can significantly increase the effective panicle number of rice and significantly improve the yield and quality of rice.After transplanting,the B40 treatment(40% Bannawangcang seedling matrix + 60% red soil)increased the effective panicle number of rice by 4.01%,and increased the yield of rice by5.07 %,with obvious effects(P < 0.05).In grinding and appearance quality,taste and nutritional quality and starch viscosity(RVA)characteristics of B40 treatment(40%Bannawangcang seedling substrate + 60% red soil)increased significantly,can effectively improve rice taste.4.Under the conditions of dry rice seedling raising in Menghai rice region,by adding fungicides(chlorothalonil or carbendazim)and nutrient elements(zinc sulfate or anhydrous potassium silicate)to the seedling substrate respectively,it was found that the height of rice seedlings decreased with the increase of the amount of fungicides,and increased first and then decreased with the increase of the amount of nutrient elements.When chlorothalonil0.5 g/kg(D2 treatment)and zinc sulfate 2.5 mg/kg(F2 treatment)were applied respectively,the stem base width and root activity were increased,making the seedlings short and strong with strong rooting ability.The compound seedling strengthening agent formed by compounding fungicide and nutrient elements can effectively increase the stem diameter,leaf sheath length and lateral root number of seedlings,increase the dry weight of 100 seedlings,and cultivate robust seedlings to meet the needs of machine transplanted seedlings.Under these experimental conditions,the most suitable amount of compound seedling strengthening agent was K3 treatment(the concentration was 2 g/kg).Compared with the control group,the plant height,SPAD value,lateral root number and 100 plant dry weight of K3 treatment increased by 32.01%,18.6%,31.32% and 57.14% respectively,and the effect was significant(P < 0.05).5.Under the field condition after transplanting dry seedling of Menghai early rice,integrated seedling-raising technology(application of seedling-raising substrate and addition of composite seedling-raising agent)treatment had significant effect on dry matter of stem and sheath,leaf and panicle of rice.During the main growth stages of rice,the application of seedling-raising matrix and the addition of compound seedling-strengthening agent had significant regulatory effects on dry matter accumulation and distribution in different organs of rice.It also promoted the absorption and accumulation of nutrients in rice plants.The accumulation of N,P,K,Zn,Fe,Mg and other elements was higher than that in the control group(CK)treatment,which could increase the effective tillering of rice plants,promote the accumulation and distribution of dry matter,increase the seed setting rate and the number of effective panicles per unit area,thereby effectively improving the yield and quality of rice.Under the field conditions after transplanting,the application of seedling-raising substrate and the addition of compound seedling-strengthening agent could effectively promote the dry matter accumulation of stem sheath,leaf and panicle of rice.The effective panicle number of BZ treatment and BZP treatment increased by 10.31% and14.48% compared with the control group(CK)treatment,respectively,and the yield per unit area increased by 15.31% and 19.97% compared with the control group(CK)treatment,respectively(P < 0.05).In summary,compared with the treatment of only applying seedling-raising substrate,the treatment of adding compound seedling strengthening agent had better effects on increasing yield,improving rice nutrition and eating quality.In summary,40% Bannawangcang seedling matrix + 60% red soil formula could effectively improve the seedling morphology,seedling quality,seedling index,root-shoot ratio and growth function of Menghai rice.After transplanting,it can also significantly improve rice yield and quality.The application of 2 g/kg special compound seedling strengthening agent could effectively increase the stem diameter,leaf sheath length,lateral root number of Menghai rice seedlings,and increase the dry weight of 100 seedlings,so as to cultivate healthy seedlings to meet the needs of mechanical transplanting seedlings.The final integrated seedling-raising technology for fragrant rice in Menghai can effectively promote dry matter accumulation,nutrient absorption and accumulation,increase seed setting rate and effective panicles per unit area in the field growth period of Menghai rice,thereby effectively improving rice yield and quality.In order to meet the needs of factory and mechanized production of Menghai fragrant rice,ensure high quality rice output,and help the scale and industrialization of Menghai fragrant rice.