Assessment of wheat variety distinctness using SSR markers

Assessment of variety distinctness is important for both the registration and the protection of particular variety. However, the current testing system, which assesses a range of morphological characters of each pair of varieties grown side-by-side, is time-consuming and is not suitable for the assessment of hundreds of samples. The objective of this study was to develop a procedure for the assessment of wheat variety distinctness using simple sequence repeat（SSR） markers. A comparison between the molecular and morphological profile of 797 varieties was made. On the basis of the comparison, pairs of varieties with a genetic similarity value（GSV） ≤90% were deemed to be distinct, accounting for ~85% of varieties assessed in wheat regional trials. For the remaining ~15% of varieties, GSVs between different varieties were 〉90%, among which ~35% were not distinct and the other ~65% were distinct. Therefore, if given a GSV〉90%, the pairs of varieties should be morphologically assessed in the field. To avoid any errors in the assessments, we proposed the elimination of contaminant plants from the sample before comparing the varietal genotypes, scoring of the genotype at each locus with a pair of allele numbers when constructing a molecular profile, and faithfully recording two alleles at a non-homozygous locus. To reduce the workload and cost, a three-grade markers comparison among varieties is suggested. In addition, 80 SSR markers and a technical procedure for assessment of wheat variety distinctness have been proposed. Based on the procedure, the distinctness assessment of ~85% of all wheat varieties is completed in our laboratory annually. Consequently, total field assessment has been reduced considerably.

Analysis on evolution of wheat variety in Henan

The essential factor that affects wheat production is variety. The paper reviews the history of fifty seven years since establishment of China about evolution of wheat variety in Henan and divides it into four periods according to historical background and nine generations in terms of developing trend of wheat variety evolution. The analysis on characteristics and influence of wheat variety evolution to wheat production indicates the regulation and contribution of wheat variety evolution, which provides reference for breeding, extending and updating of wheat variety in Henan.

Analysis on Marginal Superiority and Yield of Different Wheat Varieties in Wheat-cotton Intercropping System

In wheat-cotton intercropping system,the spike number per unit area,grains per spike,thousand-grain weight and yield of side line and inner line were investigated in six wheat varieties to study the marginal superiority and select suitable wheat varieties intercropped with cotton.The results showed that Xingmai No.4had obvious marginal superiority with the yield of 6 919.0 kg/hm2,so it was the suitable variety for wheat-cotton intercropping system.

An Analysis on Utilization of Wheat Varieties in Henan Province

The new wheat varieties with more than 6.67x104 hm2 of planting area in Henan Province during 2007-2017 were analyzed. The results showed that in the past eleven years, there were total 43 varieties from 23 breeding units of which the annual planting areas were more than 6.67x104 hm2. Among them, the annual planting areas of 13 varieties from 7 breeding units exceeded 3.33x10 hm2. The total cultivation area of 43 wheat varieties accounted for about 80% of the total wheat cultivation area in Henan in that year. Most of the varieties come from provincial universities and research institutes and municipal agricultural academies, Zhengmai 9023 was the spring wheat variety that had the largest annual and accu- mulated cultivation area, and Aikang 58 was the semi-winter wheat cultivar with the largest annual and accumulated planting area. Semi-winter varieties were the domi- nator. Among the wheat varieties planted in large area in Henan Province, medium- gluten and state-approved varieties are dominant; and provincial and municipal academies are the breeders of the major wheat cultivars in Henan.

An Innovative Project of Wheat Breeding

The objectives of wheat breeding in Sichuan and Chongqing were incon- sistent with the requirements of wheat production in 1980s. The new direction, to breed new wheat variety with high and stable yield, good quality, resistance to dis- eases, tolerance to spike sprouting, large head, white and big grain and outstanding commercial property, was put out in this article based on the development of wheat production, market economy and the needs of people. Depending on the selection and breeding work of Mianyang Institute of Agricultural Sciences for more than 20 years, new wheat varieties Mianyang 25, Mianyang 26, Mianyang 27, Mianyang 28, Mianyang 31, Xikemai 1 and Xikemai 6 were developed successively, which made a great contribution to the wheat breeding wheat breeding and production in SJchuan and even in China and the national food security.

Study on Selection of Wheat Varieties for Noodle Production in Hebei Province and Factors Affecting the Processing Quality

[Objectives]To screen out the specific wheat varieties for noodle production in Hebei Province and analyze the factors affecting the processing quality of noodle.[Methods]The quality characteristics of grains,flour and noodle of major medium gluten wheat varieties in Hebei Province were detected and analyzed.[Results]The sensory score of noodle is significantly positively correlated with wet gluten content of medium gluten wheat flour,and extensile length,cohesiveness,resilience,elasticity,gumminess,chewiness and extensile distance of TPA of noodle,and is significantly negatively correlated with softening degree.TPA of noodle can indirectly reflect sensory quality of noodle.[Conclusions]Han 7086,Xingmai 4,Liangxing 66,Shiyou 17,Heng 5229 and Liangxing 99 are suitable for producing high-quality noodle,and they can be used as noodle-specific varieties for promoting in Hebei Province.

Wheat Yield Response to Foliar Fungicide Application against Leaf Rust Caused by Puccinia triticina

A study was conducted on reducing the yield loss of wheat due to leaf rust caused by Puccinia triticina with foliar application of fungicides during the 2014-2015 and 2015-2016 growing seasons at the Wheat Research Institute in Faisalabad, Pakistan. Three fungicides： Folicur （tebuconazole） at 300 mL/ha, Nativo （tebuconazole ＋ trifloxystrobin） at 300 g/ha and Tilt （propiconazole） at 500 mL/ha were applied single or two times to Morocco and Sehar-06 wheat varieties used in the trial. The trial plots were first sprayed at the Zadok＇s scale （ZS） 3 stage and second sprayed between ZS 4.3 and 5.4 stages. The greenness of the trial crop was measured using GreenSeeker. Foliar application of fungicides significantly reduced the loss of grain yield and 1,000-grain weight （TGW） of wheat due to leaf rust in comparison to the control without fungicides application. Of the three fungicides, two times spray of Nativo reduced the grain yield loss of leaf rust susceptible mega wheat variety Sehar-06 by 45%-56% and the loss of TGW by 42%, also giving the highest marginal return in the trial. Single application of Nativo was equally effective as two times spray of Folicur in reducing the loss of wheat grain yield. Two times spray of Folicur was found to be the second choice of fungicide for reducing the yield loss of wheat. The research identified suitable fungicides for reducing the yield loss of wheat due to leaf rust and also generated important scientific knowledge required to manage a sudden outbreak of leaf rust to ensure food security.

Allelic Variation of Glu-A1, Glu-B1 and Glu-Dl in Chinese Released Wheat Varieties in the Last 50 Years

: The high-molecular-weight glutenin subunit (HMW-GS) components from about 85 varieties were fractionated by SDS-PAGE, including 22 corner stone breeding parents, 45 varieties taking important role in Chinese wheat production and 18 varieties with good bread making quality. The 22 corner stone breeding lines carry either null (c) or l(a) summits on Glu-Al loci. Five types are detected on Glu-Bl, which are 7 + 8(b), 7 + 9 (c), 14 + 15 (h), 17 + 18 (i), 6 + 8 (d). 7 + 8 and 7 + 9 are the two major types. Six types have been detected on Glu-Dl, which are 2 + 12 (a), 2 + 10 (e), 5 + 10 (d), 4 + 10 (j), 4 + 12 (c), 2 + 11 (g). 2 + 12 and 2 + 11 are the two major types. In the corner stone breeding lines, early premium from American carries 5 + 10, St2422/464 from Italy carries the 14 + 15. In addition, two relatively essential varieties, Mara and Alondra carry 5 + 10. In the 45 commercialized varieties, sowed more than 666 000 ha (10 million mu) annually, only Yangmai 5 conveys the 5 + 10 on Glu-Dl, and Xiaoyan 6 and Yumai 7 carry the 14 + 15 on Glu-B1. Four varieties, Funo, Nongda 139, Zhengzhou 683 and Fan 6 convey the 17 + 18 on Glu-B1. The 18 bread wheat varieties recommended by the Ministry of Agriculture in 1992 could be classified into two groups, 5 + 10 and 14 + 15. Zhongzuo 8131 and its selections are the typical genotype of 5 + 10. Genes coding the two subunits are from either Yecora F-70 or IRN68-181. Xiaoyan 6 and its derivative varieties are the typical genotype of 14 + 15. The genes coding 17 + 18 subunits in Chinese varieties were derived from Funo or its selections. These results basically reflect allelic changes on Glu-1 in Chinese wheat varieties in the past 50 years. It is also proven that HMW-GS components may have great diversity between lines from the same cross, which causes great difference on baking quality.

Science Letters:Nutritional composition of Pakistani wheat varieties

Pakistani wheat varieties are grown over a wide agro-climatic range and as such are anticipated to exhibit yield and quality differences. It is therefore necessary to investigate the nutritional status of wheat varieties in terms of biochemical and physiochemical characteristics available for food and nutritional purposes in Pakistan. The result shows that wheat grains of different varieties contain a net protein level of 9.15%～10.27%, 2.15%～2.55% total fats, 1.72%～1.85% dietary fibers, 77.65×10-6～84.25×10-6 of potassium and 7.70×10-6～35.90×10-6 of sodium ions concentration, 0.24×10-6～0.84×10-6 of phosphorus, 1.44%～2.10% ash, 31.108～43.602 g of thousand grain mass (TGM) and 8.38%～9.67% moisture contents. This study is significant in providing an opportunity to explore the available wheat varieties and to further improve their nutritional excellence and also essential for setting nutritional regulations for domestic and export purposes.