This paper reviews the current status, methodology, achievements, and prospects of alfalfa (Medicago sativa L.) breeding in China. There are 77 cultivars that have been registered in the country, these include 36 cultivars bred through breeding programs, 17 introduced from overseas, 5 domesticated from wild ecotypes, and 19 through regional collection/breeding programs. Cultivars have been selected for cold resistance, disease resistance, salt tolerance, grazing tolerance, high yield, and early maturity. Most of these cultivars have been developed through conventional breeding techniques, such as selective and cross breeding, and some are now being evaluated that have been developed through the application of transgenic technology. The major problems for alfalfa breeding in China include low success rate, slow progress to breed resistant varieties, lack of breeding materials and their systematic collection, storage and evaluation, lack of advanced breeding techniques, and low adoption rate of new cultivars. There are gaps in alfalfa breeding between China and the developed world. Improvement of alfalfa breeding techniques, development of cultivars with adaptations to different regions within China, and the protection and utilization of alfalfa germplasm resources have been identified as major strategies to improve the efficiency of alfalfa breeding in China.
Forty-seven lucerne varieties/lines were examined to quantify their morphological, production characteristics, and nutritive values in southeastern Australia. The experiment was established in 2015 with a randomized complete block design and four replications. The morphological and production characteristics were measured from January to October 2017, and nutritive values were measured in February 2017. The results showed that the cultivars differed significantly (P < 0.01) in morphological, production characteristics, and nutritive values. Total herbage yield was highest for Haymaster 7 (14,186 kg/ha) and lowest for Qingshui (5927 kg/ha). Plant height was highest for Cropper 9.5 (31.4 cm) and lowest for Qingshui (14.5 cm). SF 714QL had the greatest branch number (44.7 branches/15 cm row segment). AV1001 had longest leaf (2.3 cm) and greatest leaf area (16.68 cm 2 /10 leaves) whereas Force 10 and SARDI 10 SERIES 2 had widest leaves (1.3 cm). AV1005 had the highest leaf-to-stem ratio (5.64). Crude protein (CP) content was highest for SARDI 10 SERIES 2 (15.1%) and lowest for SF 714QL (8.0%). AV12 was highest in crude fat (4.5%). Neutral detergent fiber (NDF) content was lowest in Stamina 5 (33.5%). Acid detergent fiber (ADF) content was lowest in Gannong 4 (29.3%). Relative feed value (RFV) was highest in Force 11 (193.0%). Calcium (Ca) content was highest for Titan 5 (1.8%). Phosphorous content was highest for AV1 and Gannong 6 (0.1%). Overall,
Background
The saline-alkali soil area accounts for over 1/4-1/5 of the land area in Gansu Province of China, which are mainly distributed in the north of Hexi corridor and Jingtai basin. The unique ecological environment contains unique and diverse microbial resources. The investigation of microbial diversity in saline environment is vital to comprehend the biological mechanisms of saline adaption, develop and utilize microbial resources.
Results
The Illumina MiSeq sequencing method was practiced to investigate the bacterial diversity and composition in the 5 subtypes and 13 genera of saline-alkali soil in Gansu Province, China. The results from this study show that Proteobacteria, Bacteroidetes, Actinobacteria, Firmicutes, and Gemmatimonadetes were the dominant bacterial groups in 13 saline soil. Proteobacteria had the greatest abundance in sulfate-type meadow solonchaks and orthic solonchaks, chloride-type orthic solonchaks and bog solonchaks, sulfate-chloride-type, chloride-sulfate-type, and sulfate-type dry solonchaks. Halobacteria was the dominant bacterial class in soil samples except for sulfate-type meadow solonchaks and orthic solonchaks, chloride-type orthic solonchaks and bog solonchaks. The richness estimators of Ace and Chao 1 and the diversity indices of Shannon and Simpson revealed the least diversity in bacterial community in sulfate-chloride-type orthic solonchaks.
Conclusions
The sulfate anion was the most important driving force for bacterial composition (17.7%), and the second most influencing factor was pH value (11.7%).
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