瓜棉复合群体对棉花根系的影响

采用整体挖掘冲洗法和图像扫描分析方法,研究瓜棉套作模式下棉花根系在水平0～40 cm、垂直0～80 cm土壤范围内的动态分布及根系特征参数。结果表明,水平方向上,苗期根系主要分布在0～5 cm,蕾期在0～15 cm,花铃期至吐絮期在0～20 cm;垂直方向上,苗期根系主要分布在0～10 cm,蕾期在0～20 cm,花铃期在0～30 cm,吐絮期在0～40 cm。套作棉苗期和蕾期总根长和根表面积小于单作棉,至吐絮期超过单作棉;套作棉苗期和蕾期根总体积小于单作棉;套作棉蕾期和花铃期根系干物质质量小于单作棉。套作棉蕾期、花铃期、吐絮期根系干物质质量与茎粗呈极显著正相关。     

生物炭对不同连作年限棉田土壤微生物数量的影响

通过盆栽试验并利用生物炭技术研究了湖北潜江周矶农场不同连作年限棉田土壤的微生物情况,采用平板稀释法分别在苗期、蕾期、花铃期和吐絮期对土壤细菌、真菌和放线菌数量进行测定。结果表明,添加生物炭处理可有效提高不同连作年限棉田细菌、真菌和放线菌的数量,而20 t/hm~2(C1)生物炭处理可有效提高细菌和放线菌的数量,40 t/hm~2(C2)生物炭处理可更有效提高真菌数量。从不同生育时期来看,苗期微生物数量最少,在蕾期和花铃期是微生物数量繁殖的高峰期,吐絮期微生物数量开始下降。     

氨基寡糖素和乙蒜素协作防控新疆棉花黄萎病效果

为明确利用氨基寡糖素增强棉花自身抗逆性,辅以乙蒜素杀菌协作来缓解棉花黄萎病蔓延危害方案的效果,完善新疆棉花黄萎病防控技术,2021年在新疆生产建设兵团第六师芳草湖农场、第七师130团、第八师143团设计25%(质量分数,下同)寡糖·乙蒜素微乳剂1 000倍液于棉花苗期、蕾期、花铃期各喷雾1次和5%氨基寡糖素水剂1 000倍液于苗期、蕾期、花铃期各喷雾1次+头水、初花期每666.7 m²用80%乙蒜素乳油100 m L各滴施1次2种处理方案,并设空白对照(喷施清水),开展了药后苗期、蕾期、花铃期农艺性状调查和蕾期、花铃期和收获期黄萎病病情调查,并进行比较分析。结果显示,总体上2种用药方案对棉花的生长发育均无显著影响,收获期5%氨基寡糖素1 000倍液喷施3次+80%乙蒜素滴施2次处理对棉花黄萎病的防治效果最高为71.44%,25%寡糖·乙蒜素1 000倍液喷施3次对棉花黄萎病的防治效果最高为47.17%。表明新疆棉花生产中,苗期、蕾期、花铃期用5%氨基寡糖素水剂1 000倍液各喷雾1次+头水、初花期每666.7 m2用80%乙蒜素乳油100 m L各滴施1次对棉花黄...     

黄河流域棉区北部机采棉田恶性杂草的化学防除研究

影响黄河流域棉区北部棉花机械采收的恶性杂草主要有藜、反枝苋、铁苋菜、龙葵、苘麻、田旋花、打碗花和裂叶牵牛等。于2013、2014、2016年研究了这些杂草的化学防除方法。苗蕾期用嘧硫草醚和三氟啶磺隆对藜、反枝苋、龙葵、苘麻、田旋花、打碗花的防效较好,药后30～40 d的株防效超过95%;对铁苋菜和鹅绒藤的防效较差,同期株防效不足85%;对裂叶牵牛的防效居中,同期株防效为84%～94%。花铃期用嘧硫草醚和三氟啶磺隆对上述恶性杂草的防效下降;而乙氧氟草醚的杀草活性较强,药后25～40 d株防效可达100%（裂叶牵牛除外）。草甘膦在苗蕾期、花铃期和吐絮期对各种恶性杂草的株防效均在95%～100%（花铃期的裂叶牵牛除外）。上述处理对棉花均未产生明显药害,对产量也无显著影响。针对黄河流域棉区机采棉田,苗蕾期应用嘧硫草醚或/和三氟啶磺隆,花铃期应用乙氧氟草醚或草甘膦,吐絮期应用草甘膦,可较好地防除恶性杂草。     

河西走廊棉区烟粉虱的发生与防治

烟粉虱是近年来侵入河西走廊棉区的重要害虫 ,为害后棉花产量下降 ,品质变差 ,发生严重的田块减产达到 43% ,枯死株率 90 % ,其发生面积呈逐年上升趋势 ,以敦煌市发生较重 ,金塔、安西两县轻度发生 ,已成为生产上亟待解决的问题。因此 ,2 0 0 4年在敦煌市吕家堡乡进行了烟粉虱的综合防治示范 ,成效显著 ,示范点较对照田增产达1 0 %～ 40 %。1发生原因烟粉虱属侵入性害虫 ,棉区大面积的蔬菜大棚为其提供了越冬场所 ,加之针对性的综防体系尚未形成 ,农户有盲目用药的倾向 ,导致天敌减少 ,害虫抗药性增强 ,造成了较大的为害。2为害特点烟粉虱可…     

鲁西南棉花生育期连阴雨变化特征分析

利用鲁西南地区气象观测站1981-2011年的气象资料,分析了鲁西南棉花生育期间气候变化特征。结果表明：播种-出苗期、花铃期连阴雨出现概率逐渐减少,棉花蕾期、吐絮期连阴雨有逐渐上升趋势;蕾期连阴雨次数与棉花衣分、吐絮期连阴雨次数与棉花铃重呈显著负相关。     

棉花叶片叶绿素含量与纤维品质关系分析

通过对不同品种纤维品质和棉花各生育时期叶片叶绿素的测定,分析棉花叶片中叶绿素含量的高低对棉纤维品质的影响。结果表明:所有品系的叶片叶绿素含量在蕾期和花铃期的表达量高于其他时期,且品质优良的品系(纤维长度大于或等于31.00 mm、断裂比强度大于或等于30.0c N/tex和整齐度大于或等于85.0%),其苗期子叶叶绿素含量相对较高、在蕾期的叶绿素含量高于其他品系,而在花铃期的叶绿素含量则低于其他品系。不同马克隆值棉花品系叶绿素含量均在花铃期达到最大,且马克隆值在3.7~4.2时,其蕾期真叶叶绿素含量低于其他品系,而花铃期高于其他品系。     

转Bt棉田Q型烟粉虱消长动态及黄板诱杀技术

为探索预测和治理抗虫棉田Q型烟粉虱的技术,2013年对不同转Bt抗虫棉田Q型烟粉虱成虫消长动态进行了系统调查,并进行了黄板诱杀技术和效果研究。结果表明,抗虫棉与常规棉田Q型烟粉虱始发期基本一致,但抗虫棉田烟粉虱种群盛发期较常规棉稍推迟,且种群发生量显著高于常规棉田;另外,不同抗虫棉之间Q型烟粉虱种群消长动态也不太一致。黄板诱杀棉田Q型烟粉虱技术和效果研究结果表明,当黄板下沿与棉株生长点平行放置,放置方向为东西走向,粘着剂为机油时,诱杀效果最佳。该研究为抗虫棉田Q型烟粉虱的预警监测和无公害治理,提供了一定的理论依据和技术支撑。     

用半致死温度法鉴定北疆不同时期主栽棉花耐寒性

为了解北疆棉区不同时期代表性棉花品种的耐寒性,分别在苗期、盛蕾期、花铃期、吐絮期对28个棉花品种的叶片进行－2 ℃、－4 ℃、－6 ℃、－8 ℃、－16 ℃的低温胁迫,测定其电导率,计算半致死温度（LT50）,对其耐寒性进行鉴定评价。结果发现28个棉花材料LT₅₀的范围为：苗期－9.07～－0.12 ℃;盛蕾期－4.43～4.25 ℃;花铃期－4.02～9.69 ℃;吐絮期：－15.76～3.06 ℃。所有材料不同生育期的LT50平均表现为花铃期＞盛蕾期＞吐絮期＞苗期,且差异显著。中J9645和新陆早35号属于全生育期高耐寒品种,新陆早26号属于全生育期冷敏感品种。研究探讨了LT₅₀在棉花耐寒性鉴定上的应用,筛选出了不同生育期耐寒的棉花品种,提出分别以－4 ℃、－2 ℃、2 ℃、－4 ℃为苗期、盛蕾期、花铃期、吐絮期棉花耐寒性指标的临界温度,并建立了不同生育期棉花耐寒性标准,对棉花耐寒性研究具有重要意义。     

棉花丰产栽培技术

根据棉花的生物学特性和生长发育规律，在栽培技术上主要分苗期、蕾期、花铃期、吐絮期的分阶段栽培管理措施。     

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.     

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.     

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。     

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.     

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。