镉胁迫下甜、糯玉米开花期性状的全基因组关联分析

以183份甜、糯玉米自交系构成的关联群体为材料,在2种Cd污染水平下对甜、糯玉米开花期(DA,days to anthesis)、吐丝期(DS,days to silking)和开花吐丝间隔(ASI,anthesis silking interval)进行全基因组关联分析,以揭示重金属Cd胁迫对甜、糯玉米开花期的影响及调控基因。结果表明:不同Cd污染水平对甜、糯玉米DA和DS均产生影响,其中对DS的延长更为明显,从而导致ASI的增大。同时,甜玉米ASI平均值高于糯玉米ASI,由此表明甜玉米ASI对重金属Cd胁迫更为敏感。结合群体基因型和开花期相关性状表型的全基因组关联分析,分别筛选到3个开花期相关的SNP位点和6个吐丝期相关的SNP位点。根据其所对应的物理位置与Maize GDB和NCBI基因数据库进行比对,预测获得8个已知功能基因,其中包括在前人研究中与玉米开花期有关的候选基因。以上研究解析甜、糯玉米在重金属Cd污染水平下开花期及吐丝期的遗传规律,为今后开展甜、糯玉米分子标记辅助育种和Cd安全品种的选育提供参考。

不同鲜食甜、糯玉米品种区域试验

种植甜、糯玉米是山西省忻州市农业产业结构调整的主要方向之一。2017年在忻州市进行国家级区域试验,对10个甜、糯玉米品种(含对照品种)的农艺性状、抗性、产量及果穗性状等进行了比较分析,为进一步提高该区域甜、糯玉米的种植效益提供理论指导。结果表明,相比对照品种京科糯569,白糯型京科糯2000E的鲜穗丰产性最高,鲜籽粒丰产较差,抗性较高,综合性状表现良好,适合采收鲜穗;白甜糯型农科糯336和黄甜糯型黄糯9号的丰产性整体较高,抗性较高,综合性状表现优异,采收鲜穗和鲜籽粒均可。因此,该区域可针对不同的产品需求决定品种的推广应用。

NaCl胁迫对甜、爆、糯玉米幼苗有机渗透调节物质的影响

以特用玉米品种沈糯6号、沈爆3号和沈甜6号为试材,设置5个梯度的NaC l盐溶液(0mmol/L、50mmol/L、100mmol/L、150mmol/L、200mmol/L)对玉米幼苗从三叶一心时开始胁迫处理1周,对部分有机渗透调节物质进行了研究。结果表明:随着NaC l浓度的增加,沈甜6号和沈爆3号的游离氨基酸含量变化趋势较一致,呈现双峰状增长,都在50mmol/L时出现最大峰值;沈糯6号为单峰状增长,在NaC l浓度为100mmol/L时有最大值;3个品种的可溶性蛋白质含量在盐浓度低于150mmol/L时均不同程度地降低,之后又都开始上升;可溶性糖含量在盐浓度低于150mmol/L时增长趋势基本一致,均呈现单峰型增长,之后沈糯6号急剧下降,沈爆3号和沈甜6号开始上升;3个品种脯氨酸含量随NaC l浓度的增加也不同程度地增加。150mmol/L的盐浓度是3个品种的耐盐临界点。从总体水平看,沈糯6号较耐盐,沈甜6号最弱。

甜、糯玉米无公害栽培配套技术探讨

近年来,国内对于甜、糯玉米的需求量一直在不断增加,其种植面积也开始越来越大,尤其是早春甜、糯玉米更是有着质量高、品质优、效益好的特点,得到了快速的发展。为了更好地顺应发展的需要,在其试验示范的基础上,通过详细的调查研究,对甜、糯玉米无公害栽培配套技术进行了有效的分析和探究,以期指导生产。

甜、糯玉米各生育时期主要病虫害及防治分析

甜、糯玉米与普通玉米相比,种子活力相对较低,苗期长势较弱,生长状况较差,采用农业措施切断病害传染源和健康栽培技术,选择使用高效、低毒、低残留的化学农药进行药剂防治。

应用优质甜、糯玉米高效栽培技术提高土地使用效益

本文论述了应用优质甜、糯玉米高效栽培技术提高土地使用效益。

山南市鲜食甜、糯玉米新品种引种试验

为筛选出适宜山南市沿江谷地种植的鲜食甜、糯玉米新品种,满足生产和市场消费对优良品种的需求,特从内地引进9个鲜食甜、糯玉米新品种,在山南市乃东区开展品种大区对比试验,试验结果显示:研究区露地地膜覆盖、育苗移栽种植鲜食甜糯玉米宜选用生育期在130 d以内的品种,参试品种“SHZR270”“雪甜7401”“金银早2020”“华甜玉3号”“雪甜232”“SHZR281”的生育期适宜、外观品质优、穗大粒满、农艺性状好,可在同生态区推广种植;结合气象资料推测,保温育苗的适宜播种期在4月下旬至5月初。

探究阳山县普通杂交玉米、甜玉米、糯玉米新品种的试验研究

玉米是阳山主要粮食作物,是广东省玉米种植面积大县之一。由于阳山县种植玉米品种良萎不齐,更有个别玉米种子经销商推销未经审定和试验示范种子直接推广市场。文章针对阳山县普通杂交玉米、甜玉米、糯玉米新品种的试验展开了研究。

“白菜、糯玉米—稻—蒜苗、芫荽”复种多熟栽培技术

总结了"白菜、糯玉米—稻田—蒜苗、芫荽"复种多熟制高产栽培技术,总结出在不同地区科学合理安排最佳茬口和配置的种植品种,在单位有效面积上获高产、高效、低投入的种植模式,以期为晴隆县农业经济增长提供科学依据。

基于SLAF-seq技术分析甜、糯玉米种质遗传多样性

利用简化基因组测序技术SLAF-seq,对国内外引进选育的81份鲜食甜、糯玉米自交系进行遗传多样性分析。结果表明,共获得803 058个SLAF标签,其中,多态性SLAF标签373 764个。通过序列分析,获得169 128个有效单核苷酸(SNP)多态标记,利用这些SNP标记分析和构建了81份鲜食甜、糯玉米资源的群体结构和系统发生树,并将其分为2个群。结果表明,简化基因组测序技术SLAF-seq能高效、低廉地开发出大量SNP标记,是作物种质资源群体遗传分析的有效工具。研究结果为甜玉米不同基因的聚合、温-热种质杂交育种、鲜食甜、糯玉米亚种间杂交育种提供依据,有利于鲜食甜、糯玉米自交系的高效利用、品种选育及杂种优势群的建立。

沂源县种植甜糯玉米的气候条件分析

通过对甜、糯玉米生长发育与沂源县气候条件的对应关系分析,总结出影响其产量高低的气候因素,并提出相关建议,以达到充分利用气候资源,减轻气象灾害,提高甜、糯玉米在沂源的产量和品质以及种植面积的目的。

广东旱地作物品种改良技术研究初报

介绍了广东省旱地作物品种改良技术研究团队在甜、糯玉米、花生、甘薯、大豆等广东主要旱地作物品种改良关键技术研究方面的最新进展,包括资源的收集引进、鉴定创新、核心种质构建、品种改良技术体系的建立、良种繁育与种子质量控制关键技术研究及新品种的示范推广等。

Reasearch on Occurrence Rules of Asian Corn Borer Ostrinia furnacalis in the Field of Waxy Corn

[Objective] This program aimed at providing basis for timely and effective control of Asian corn borer Ostrinia furnacalis in waxy corn fields through investigations and researching on occurrence and damage characteristics of Ostrinia furnacalis in the main producing area of waxy corn of Shanxi Province.[Method] Attraction and collection of the adults,fixed-points and random investigations on eggs and larvae were the main methods in this research.[Result] Ostrinia furnacalis appeared in two generations per year in the field of waxy corns,the generations were basically nonoverlapping with significant interval.The peak period of the overwintering generation adults in the field of waxy corn was early to middle of June,peak period of the first generation adults was from early August to late August;peak period of the first generation eggs was from the end of early June to the binning of late June,the peak period of the second generation eggs was from the middle of early August to late August.Egg-laying performances of Ostrinia furnacalis on waxy corns in different growth period suggested that the temptation of waxy corns to egg-laying of Ostrinia furnacalis had gradually increased with the continuation of growth stages before the heading of waxy corns;while after the heading of waxy corns,the temptation of waxy corns to egg-laying of Ostrinia furnacalis had gradually reduced with the continuation of growth stages.The amount of eggs on waxy corns was more than eggs on normal corns with the same growth period and growth conditions.The first generation of Ostrinia furnacalis caused more serious damages than the second generation.The first generation larvae caused more serious damages on waxy corns with early sowing period than with middle sowing period,while the late sowing fields basically uninjured.The early sowing and middle sowing corns were damaged but lightly,due to the slight occurrence of the first generation larvae.The second generation larvae caused more serious damages in late sowing waxy corn field than in middle sowing waxy corn field.As the early sowing waxy corns were harvested before the beginning of damage peak period of the second generation larvae,they were basically uninjured or slightly damaged by the second generation larvae in general years.Because the second generation larvae were in large-scale occurrence,they had caused serious damages to late and later middle sowing waxy corns.Incidence of ear rot disease on the female ears of waxy corns was closely related to the damages of Ostrinia furnacalis on ears,which was higher on the ears infested by Ostrinia furnacalis.[Conclusion] Comprehensive control on the second generation of Ostrinia furnacalis in the mid and late sowing field of waxy corn should be strengthened.

Correlation and Principal Component Analysis on Main Agronomic Traits of New Waxy Corn Varieties

[Objective] This study was conducted to provide certain theoretical reference for the comprehensive evaluation and breeding of new fresh waxy corn vari- eties. [Method] With 5 good fresh waxy corn varieties as experimental materials, correlation analysis and principal component anatysis were performed on 13 agronomic traits, i.e., plant height, ear position, ear weight, ear diameter, axis diameter, ear length, bald tip length, ear row number, number of grains per row, 100-kernel weight, fresh ear yield, tassel length, and tassel branch number. [Result] The principal component analysis performed to the 13 agronomic traits showed that the first three principal components, i.e., the fresh ear yield factors, the tassel factors and the bald top factors, had an accumulative contribution rate over 87.2767%, and could basically represent the genetic information represented by the 13 traits. The first principal component is the main index for the selection and evaluation of good corn varieties which should have large ear, large ear diameter but small axis diameter, i.e., longer grains, larger number of grains per ear, higher, 100-grain weight and higher plant height. As to the second principal component, the plants of fresh corn varieties are best to have longer tassel and not too many branches, and under the premise of ensuring enough pollen for the female spike, the varieties with fewer tassel branches shoud be selected as far as possible. From the point of the third principal component, bald tip length affects the marketing quality of fresh corn, and during fariety evaluation and breeding, the bald top length should be control at the Iowest standard. [Conclusion] The fresh ear yield of corn is in close positive correlation with ear weight, 100-grain weight, ear diameter, number of grains per row and ear length, and plant height also affects fresh ear yield.

Analysis on Waxy Corn/Soybean Intercropping Pattern and Economic Benefit

The research mainly analyzed effects of waxy corn/soybean intercropping on yields of the two crops, as well as agronomic characters, and the economic benefits of the mode. The results showed that although yields of waxy corn and soybean went down by 21.19% and 31.04% per unit area, land equivalent ratio（1.48） kept higher than 1, suggesting the intercropping improves land use rate. Besides, due to the practice of intercropping, many characters of waxy corn grew, but of soybean declined. The economic benefits from high to low were waxy corn/soybean intercropping, monoculture of waxy corn, and monoculture of soybean.

Analysis on Genetic Characteristics of Leaf Angle in Waxy Corn

The leaf angle in waxy corn is a significant trait for breeding corn with compact plant type, which is beneficial to improve yield. According to the Griffing method II, the GCA （general combining ability） and SCA （specific combining ability） of leaf angle trait in the 7 waxy corn inbred lines and 21 combinations were esti-mated, and the genetic characteristics of leaf angle in corn were also analyzed. The results showed that among the 7 inbred lines, the GCA values ranked as N22 〉N8 〉 N28 〉 N7 〉 N23 〉 N27 〉 N4. The GCA of N27 showed great negative ef-fect, and the genetic variance of its SCA was lower. It suggested that the N27 can be used as an ideal parent for breeding excel ent combinations with smal leaf angle and compact plant type. The inheritance of leaf angle trait in waxy corn is in ac-cordance with the model of ＂additive - dominant - epistatic＂. The efficiency of leaf angle trait is control ed by recessive genes. The broad heritability of leaf angle trait in waxy corn is relative low （68.5%）, but its narrow heritability is relatively high （72.62%）. In the breeding practices, the early-generation selection is more suitable for the leaf angel trait.

Herbicide Safeners Increase Waxy Maize Tolerance to Nicosulfuron and Affect Weed Control

Safeners are an important tool used to ensure the safe using of herbicide. This research was conducted to determine the effects of nicosulfuron alone and in combination with herbicide safeners on waxy maize （Zea mays L. var. ceratina Kulesh） injury, as well as on barnyard grass （Echinochioa crus-galli） and large crabgrass control （Digitaria sanguinalis L. Scop）. Whole-plant experiments were conducted under laboratory condition, by using post emergence treatment with safeners and nicosulfuron. The results showed that the herbicide safeners isoxadifen-ethyl （IE） and cyprosulfamide （CS） were more effective in reducing waxy maize injury from nicosulfuron than fenchlorazole-ethyl （FE）, cloquintocet-mexyl （CM） and mefenpyr-diethyl （MD）. Whole-plant dose-response experiments showed that nicosulfuron in combination with IE or CS increased its herbicidal activities against barnyard grass and large crabgrass. To confirm the result, a mixture of IE or CS and nicosulfuron were sprayed on waxy maize in the field, by using a backpack plot sprayer with a flat-fan nozzle. The mixture led to lower phytotoxicity than nicosulfuron alone. The mixture tested did not affect the maize grain weight. The results showed that IE and CS could enhance crop safety and extend the use of nicosulfuron on waxy maize.

Composition of Starch and Protein in the Endosperm of Newly Generated Double Recessive Waxy and Opaque 2 Maize （Zea mays L.） Genotypes

Waxy maize with its pure amylopectin starch is the staple food of many ethnic minorities in hilly regions of Southeast Asia （SEA）. A combination of waxy and quality protein maize （QPM） traits would improve the quality of protein of waxy maize for human consumption. Double recessive waxy-QPM （wx-o2） genotypes had been generated from Southern Chinese material by haploid induction of crosses heterozygous for the two quality traits with an absolutely conserved waxy type and an improved amino acid profile. The vitreous kernel trait （due to the additional modifier genes present in QPM） was lost in the wx-o2 plant material; this may be due to the waxy mutation, this is anyhow desirable for acceptance as waxy maize is preferred due to its soft grains. The content of the quality limiting amino acid lysine was greatly increased in double recessive wx-o2 genotypes compared to standard waxy maize, but still with a high variation among genotypes for future improvement. Conclusively, it was indeed possible to combine two grain quality mutations successfully within one genotype and prototypes of double quality wx-o2 are available now to contribute to meet human requirements in essential amino acids and thus reduce malnutrition in various regions of Asia.