2008年湖北仙桃市棉花大面积早衰的原因及对策

仙桃市地处江汉平原腹地,是湖北省主产棉县（市）之一。2008年植棉面积2．8万公顷。由于前期风调雨顺,实现了棉花“伏桃缠腰”的丰产长相,8月15日棉花生育调查,全市单株两伏桃25．5个,预计单株秋桃12．1个,单株成桃37．6个,公顷产皮棉1364kg。8月14日后气候异常,大风暴雨,气温剧变,棉花大面积早衰,近25％脱叶死亡,全市实际产量只有1140kg,减产169／6左右。     

2008年湖北仙桃市棉花大面积早衰的原因及对策

仙桃市地处江汉平原腹地,是湖北省主产棉县(市)之一.2008年植棉面积2.8万公顷.由于前期风调雨顺,实现了棉花"伏桃缠腰"的丰产长相,8月15日棉花生育调查,全市单株两伏桃25.5个,预计单株秋桃12.1个,单株成桃37.6个,公顷产皮棉1364 kg.8月14日后气候异常,大风暴雨,气温剧变,棉花大面积早衰,近25%脱叶死亡,全市实际产量只有1140 kg,减产16%左右.     

洞庭湖棉区棉花三桃齐结的高产技术措施

通过实践调研和经验总结,概述了湖南洞庭湖棉区棉花生产要抓好伏前桃、伏桃和秋桃,做到三桃齐结,满足棉花生产过程中带桃入伏,伏桃满腰和秋桃盖顶的基本要求,才能夺取棉花高产丰收.同时就三桃齐结各个生产环节的具体技术措施作了浅析.     

收获季节棉区巡展

1山东德州:棉花丰收,皮棉单产1336.5kg2006年该市共植棉14.47万hm2左右,比上年增长4.4%。由于栽培和气候条件好,提高了伏桃和早秋桃的结桃率,伏桃占75%左右。据山东德州市农业部门和棉花协会调查测算,今年德州地区棉花长势良好,衣分高、品质好、开放早,衣分36%~37%,比上年高2%左右,全市平均公顷产子棉3765kg,折皮棉1336.5kg,预计总产23.35万t。9月下旬子棉收购价为每千克5.4元左右,全市平均摘拾量在40%左右,而收购量仅10%左右。(山东德州市棉花协会马俊凯)2新疆奎屯:一二五团向安全生产要效益2006年,农七师一二五团种植的1万多hm2棉花丰收在…     

棉花种子优质高产结铃模式调节新技术

传统的棉花种子高产栽培法采用的是“壮苗早发．稳长多结．收中喷花”的技术路线．要求带桃入伏，伏桃满腰，秋桃盖顶：但经多年的棉花生产实际检验，三桃齐结很难做到。早发棉田，伏前桃结多了，到结铃盛期营养供应不上．伏桃并不多结，后期易早衰．直接影响棉种质量：晚发棉田．秋桃中的晚秋桃比例较大，后期遇低温往往铃轻子瘪．也不能达到种子高产优质的要求。     

主攻八月桃获优质高产

8月桃是指8月底以前的成桃,包括伏前桃、伏桃和早秋桃三个部分,既是优质桃,又是构成产量的主体桃,同时还是可纺棉的有用桃。8月桃在棉花总桃中所占比例应当适度,比例过高表明出现早衰,后期光、温资源得不到有效利用,棉花不能获得高产;比例过低说明棉花严重迟发,晚秋桃比例大,棉花尽管能获得一定的产量,但可纺棉比例下降,质量不优。结合枣阳市1989年以来调查资料分析,8月桃以占总成桃数的80%较为恰当。因此,鄂北岗地主攻8月桃的目标要求是:棉田收获密度每公顷3.75万株,单株果枝20个,单株成桃25个,其中8月底以前单株成桃22个左右,每公顷总桃90…     

2005年湖北省天门市棉花大面积早衰

2005年,天门市棉花生产虽然苗期受自然气候的影响,移栽推迟,管理受阻,棉苗滞发,但进入蕾期后,自然气候十分有利于棉花生长,加上市场棉价上扬,极大地调动了农民植棉积极性,棉田管理精细,实现了棉花“伏桃满腰”的丰产长相。8月15日全市棉花生育调查,单株两伏桃26.2个,创历史最高记录,预计秋桃10.95个,单株成桃34.97个,公顷产皮棉1350kg。8月中下旬,气候异常,气温剧变,阴雨寡照,全市棉花大面积早衰,近20%的田块枯萎死亡,实际产量1186.5kg,减产15%左右。1早衰的特点一是来势猛。8月14-15日雨后天晴始见症状,部分棉株叶片萎蔫青枯;8月20-23日暴…     

秋后低温阴雨对棉花生育的影响及预防技术

2005年,潜江市棉花苗期受自然气候的影响,移栽推迟,管理受阻,棉苗滞发。进入蕾期后,由于自然气候十分有利,加上棉苗管理精细,实现了棉花“伏桃满腰”的丰产长相。8月15日生育调查,单株成桃21.44个,较上年多4.21个。8月中旬后,气候异常,温度剧变,罕见的低温阴雨导致棉株根系活力下降,抗性减弱,大面积早衰,蕾铃脱落严重,同时铃病、“两萎病”发生严重,对棉花生长发育和产量影响很大。因秋桃减产11%~25%。本文仅就本市调查情况预以分析,并提出预防类似灾害的技术对策。1气候状况分析1.1温度低。8月中旬至9月上旬旬平均温度分别是27℃、26.3℃、…     

棉花增施桃肥的依据及技术

棉花进入开花结铃期以后，因苗适时适量增施桃肥，有利于棉花增结上部桃及外围桃，增加铃重，提高产量和效益。１增施桃肥的依据１．１充分利用生长季节，可防早衰，延长有效开花结铃期据１９９０－１９９３年定点苗情考察，增施桃肥的田块，８月２２日左右现的音成铃率平均为３０．７％，且能正确吐絮，有效开花结铃期较对照（未施桃肥）的田块，延长７ｄ左右。１．２改善蕾铃结构棉花高产需伏前桃，伏桃、早秋桃，晚秋桃四齐结，增施桃肥恰好满足了棉花后期生产养分的需求，有利于多结早秋桃和晚秋桃。据１９９０～１９９３年连续４年对比…     

棉花晚秋桃有效性研究

棉花晚秋桃有效性研究方陈秋（湖北省黄冈地区农校４３６１０２）湖北省习惯将棉花所结的铃，按季节划分为三种桃，７月１５日以前结的大铃，称为伏前桃，伏前桃的有无是早发与否的标志；７月１６日至８月１５日结的大铃，称为伏桃，伏桃桃大质优数量多，对棉花产量与品质...     

Factors in the Reduction in Grain Number in Winter Wheat by Early-Sowing in Yamaguchi

Abstract

Grain number per spike of wheat is lower in early sowing than in the conventional standard cultivation in Yamaguchi, Prefecture, Japan. Components of the grain number per spike in five cultivars were analyzed with respect to temperature during the spike development period throughout three growing seasons 2001/2002, 2002/2003 and 2003/2004 to find the cause of the problem of early sowing cultivation. The plants sown in early-October and late-November were called the early sown group and the standard group, respectively, in the following. Three of the five cultivars, Hokushin, Akitakko and Nanbukomugi, showed a strong winter habit, which requires very cold temperatures for spike differentiation. The other two cultivars, Iwainodaichi and Airakomugi, had a moderate winter habit. Grain number per spike and grain yield were decreased by early-sowing (compare with the standard group) in almost all cultivars throughout the three growing seasons. The three cultivars which had a strong winter habit had fewer spikelets per spike in the early-sown group than in the standard group. The other two cultivars which had a moderate winter habit had fewer grains per spikelet in the early-sown group. The higher the temperature during the spikelet formation phase, which is from flag leaf initiation to terminal spikelet initiation, the higher the number of spikelets per spike in the standard group. The spikelet number per spike in the early-sown group increased with the increase in productive tillers under fertile conditions. Such conditions also increased the grain number per spike.     

Allelopathy in Agroecosystems in Spain

Summary

This paper reviews the effects of allelopathic interactions in agroecosystems in Spain on plant physiological activity and their ecological advantages. The phenological stage of growth of donor plants and the effective allelochemicals in the soil solution while studying the role of phenolic compounds were highlighting. Finally possible future prospects and conclusions regarding weed control by allelochemi-cals under integrated crop management strategies are discussed.     

2009年中国稻米市场分析及2010年展望

以翔实的资料对2009年中国稻米生产、消费、进出口、供求平衡、库存、价格走势、购销政策和国际稻米供求等情况进行了全面地分析,对影响2010年稻米市场价格走势的各种因素进行了深入研究,并在此基础上对2010年我国稻米市场价格走势进行了预测,结论是我国稻米价格仍呈上行趋势。     

Diurnal changes in net photosynthetic rate in potato in two environments

Summary Diurnal changes in net photosynthetic rate were measured in a furrow-irrigated potato crop and in a riverbed crop where the water table was always maintained at 20–28 cm from the soil surface. In the irrigated crop, the photosynthetic rate during mid-afternoon was about half the peak rate observed at noon. This reduction was accompanied by a near tripling of stomatal resistance, a 45% reduction in transpiration, and a 5-fold increase in the difference between leaf and air temperatures. No such changes were observed in the riverbed crop where the photosynthetic rate remained nearly constant at about 0.9 mg m⁻² s⁻¹ between 9 a.m. and 4 p.m. Tuber yield in the riverbed crop was about 30% higher than in the irrigated crop.     

我国干热区甘蔗抗旱植蔗主要问题研讨

我国干热蔗区是我国甘蔗糖业的重要生产基地,蔗区光热资源丰富,唯降水分布不均成为植蔗生产的主要限制因子;根据蔗区植蔗特点和甘蔗需水规律,苗期抗旱是干热蔗区抗旱植蔗的关键,保证较多的总苗数和足够的生长量是苗期抗旱植蔗需解决的关键技术难题,制定相应的苗期抗旱植蔗栽培技术措施是解决该难题的重要保障;该观点为我国干热蔗区植蔗生产、甘蔗引育种提供理论和技术支持。     

Advances in Variable Rate Technology Application in Potato in The Netherlands

Precision agriculture is a farming management concept based on observing, measuring and responding to inter- and intra-field variability in crops. In this paper, we focus on responding to intra-field variability in potato crops and analyse variable rate applications (VRAs). We made an overview of potential VRAs in potato crop management in The Netherlands. We identified 13 potential VRAs in potato, ranging from soil tillage to planting to crop care to selective harvest. We ranked them on availability of ‘proof of concept’ and on-farm test results. For five VRAs, we found test results allowing to make a cost-benefit assessment. These five VRAs were as follows: planting, soil herbicide weed control, N side dress, late blight control and haulm killing. They use one of two types of spatial data: soil maps or biomass index maps. Data on costs and savings of the VRAs showed that the investments in VRAs will pay off under practical conditions in The Netherlands. Savings on pesticide use and N-fertilizer use with the VRAs were on average about 25%, which benefits the environment too. We foresee a slow but gradual adoption of VRAs in potato production. More VRAs will become available given ongoing R&D. The perspectives of VRAs in potatoes are discussed.     

棉花体细胞无性系变异的研究进展

体细胞无性系变异是一种重要的细胞工程育种技术,其应用于棉花育种的前提是建立高效的组织培养诱导再生植株体系.本文简要综述了棉花离体诱导植株再生研究的现状,重点讨论了棉花体细胞无性系变异的表现、利用方法及机理,提出了当前研究存在的问题并对今后的研究进行了展望.     

我国高粱育种研究进展

对我国高粱育种的主要途径和研究方向进行了概述,针对目前高粱产量徘徊现象,提出了高粱超高产育种设想,并对其技术路线进行了探讨。