苜蓿根瘤菌接种数量与方式对接种效果的影响

本研究以‘中苜1号’苜蓿和gfp-Sm1021根瘤菌为试验材料,设置3个接种量和2种接种方式,通过温室试验探究接种量和接种方式对苜蓿根瘤菌结瘤固氮的影响。结果表明:提高接种量能增加苜蓿结瘤数、地上生物量和蛋白含量,降低地下生物量。接种量增加到(1.9×10^(5))个·株^(-1)后,种子接种处理中,继续增加接种量不能提高结瘤数;沟施接种处理中,继续增加接种量能增加结瘤数但降低地上生物量。相同接种量下,沟施可提高苜蓿的结瘤数,增加的根瘤主要位于0~4 cm侧根、4~8 cm主根、4~8 cm侧根和8~12 cm侧根。0~4 cm主根、0~4 cm侧根和4~8 cm主根的根瘤固氮酶活性显著高于其它部位。综上,接种量较低时,沟施接种优于种子接种,接种量较高时,结合根瘤的分布特征和固氮酶活性,沟施接种处理中结瘤数增加带来的固氮优势下降。

花生施氮肥效果与根瘤菌固N的关系

在中等以上土壤肥力条件下，花生施氮肥均显著增加植株生长量和荚果产量，单株结果数和荚果产量分别比不施肥、不接种根瘤菌（对照）处理增加２６．９％～３６．５％和２９．９％～３４．１％。但其主、侧根上根瘤数目和根瘤菌固氮量，则随氮肥用量增加而减少，根瘤菌固氮量由８８．６％降至３０．８％。不施氮肥只接种根瘤菌的处理，根瘤菌的固氮量虽高，但植株生长量和荚果产量则明显降低，单株结果数和荚果产量仅比对照处理增加６．９％和５．９％。

刺槐根部结瘤规律初探

刺槐与根瘤菌的共生固氮作用，在林业生产中具有重要意义。文章从不同林龄、不同树种组成、不同土壤质地、不同土壤深度、林分的不同部位和不同季节的根瘤量的差别，探讨了刺槐根部结瘤的规律性。并据此提出了促进刺槐根部结瘤的营林措施。

7种豆科作物的光合作用和养分富集特征

以7种豆科绿肥作物(绿豆、小豆、乌豇豆、大猪屎豆、合萌、望江南、决明)为材料,采用大田种植和盆栽种植法,记载7种作物的生长发育特征,测定其根瘤量、产量和干物质积累效率,测定各作物在盛花期的光合特征参数和氮、磷、钾、铁、锌养分含量,筛选适宜安徽及周边地区种植的高产高效良种。结果表明:供试材料均属半灌木状草本,茎秆直立,呈圆形、多棱角或纵向小沟纹;根属直根系,主根不发达;合萌为偶数羽状复叶,望江南为偶数长椭圆形叶,大猪屎豆和决明为倒披针状叶,其他为披针状叶;大猪屎豆叶互生,其他叶对生;总状花序,浅黄色蝶形花;除大猪屎豆小花有20~30朵,无限结荚,其他供试作物的小花数有10~15朵,有限结荚;各种豆科作物的根瘤量占地下部总质量的17.5%~32.5%;乌豇豆叶片光合效率和干物质积累效率最高,分别为23.1μmol/(m^2·s)和57.0 kg/(hm^2·d);望江南鲜草、干草和种子的产量最高,分别为22 248、5 028、2 366 kg/hm^2;固氮和富集磷、铁能力最强的是望江南,而富集钾能力最强的是大猪屎豆,富集锌能力最强的是合萌。从光合效率、产量、养分富集能力等方面综合考虑,初步认为乌豇豆、望江南、大猪屎豆和合萌4种豆科作物适宜在安徽种植推广。

Effect of Rhizobium Inoculation on Phosphorus Uptake,Yield and Quality of Soybean Plants

[Objective] This study aimed to investigate the effect of inoculation with various rhizobium strains on growth status, phosphorus uptake, yield and quality of soybean plants. [Method] Using Dongnong 42 and Dongnong 46 as experimental soybeans, four treatments were designed, including non-inoculated CK group and three treatment groups inoculated respectively with rhizobium strains R2, R, and Rs, to analysis the effects of rhizobium inoculation on growth status, phosphorus uptake, yield and quality of soybean plants. [Result] Inoculation with different rhizobium strains could significantly increase the biomass and phosphorus content of the roots and shoots of Dongnong 42, to be specific, rhizobium strain R2 showed the best ef- fect, followed by Rs, and those of roots were improved greater than the shoots; in- oculation with rhizobium could significantly increase the yield of Dongnong 42, and R5 showed the best effect, but the yield of Dongnong 46 was decreased; after in- oculated with rhizobium, the protein content and fat content of soybean were signifi- cantly increased, and R2 showed the best effect, but the effects on different varieties varied, to be specific, the protein content of Dongnong 42 was significantly in- creased, while the fat content of Dongnong 46 was significantly increased; different rhizobium strains inoculated to different soybean varieties showed different effects. Inoculation with suitable rhizobium can improve plant growth characteristics, promote phosphorus uptake of plants, increase soybean yield, and effectively improve soy- bean quality. [Conclusion] This study provides theoretical basis for solving the prob- lem of soil phosphorus deficiency, increasing soybean yield and improving soybean quality in the future.

Effects of Different Nitrogen Application Rates and Methods on Root Nodule Growth and Yield of Soybean

This study was conducted wiffl a spring soybean variety Jindou 19 to test file effects of rhizobia inoculation or non-inoculation and nitrogen application rates at 0, 27, 54 and 75 kg/hm^2 （N1-4） on root nodule dry weight, root nodule number, yield and yield components of soybean. The results showed that the nitrogen fertilizer significantly affected soybean root noduce and soybean yield, the dry weight and number of root nodules increased gradually with the increase of nitrogen application rate, and the yield of file rhizobia inoculated treatment was significantly higher than that of file rhizobia non-inoculated treatment; and under file condition of file rhizobia inoculation, with nitrogen application amount at 75 kg/hm^2, file Jindou 19 performed a better nitrogen fixing effect in file growing stage, and its plot yield was 4 997.417 kg/hm^2, 4.06% higher than that of file treatment without inoculating rhizobium and 12.50% higher than that of the treatment without applying nitrogen fertilizer.