淮北地区小麦主栽品种对低温胁迫的响应及抗寒性评价

为给安徽淮北地区小麦安全生产提供指导,以当地主栽品种为材料,研究不同播期条件下小麦植株对低温胁迫的响应,结合自然低温下田间冻害情况及产量表现等,对主栽品种的抗寒性进行初步评价。结果表明,返青期-12℃以下时品种的抗寒性急剧下降;播期间小麦植株的抗寒性表现为：晚播>适播>早播;电解质渗出率均随温度的降低逐渐增大;地域间抗寒性差异明显;不同区域育成品种抗寒性强弱表现为山东省＞河南省＞安徽省;筛选出一批抗寒高产品种,如‘良星66’、‘山农20’、‘济麦22’、‘烟农19’等,可作为安徽淮北地区早播条件下种植的理想品种。     

重庆市≥10 ℃积温资源时空变化特征分析

[目的]积温是一种重要的生态环境资源和气候资源,了解积温的时空变化规律对指导农业生产和生态环境建设具有重要意义。[方法]利用重庆市34个观测站1960—2016年共57年的地面气象观测资料,选用Mann-Kendal突变检验,Morlet小波周期分析等气象统计方法,分析了重庆地区≥10℃积温资源的时间变化和空间变化规律,得出结果：[结果]重庆地区积温分布不均,沿长江和乌江分3个不同的区域分布,重庆大部分地区年均积温在5500℃至6500℃之间。1960—1980年,重庆积温变化主要表现为增温趋势。1981—2000年,积温明显减少。2000年以后,积温正负相间,变化明显加快,气候变得更加异常。重庆1区的积温,80年代以前振幅较大,80年代以后,振幅明显减小。2区和3区的积温变化趋势基本一致,变化规律基本相同,振幅也基本一致。[结论]重庆积温资源丰富,重庆江津、丰都、万州等地区完全满足一年三熟制,可以开展一年三熟制农作物耕种试点。     

Evaluation of the Low-Temperature Tolerance of Cotton Varieties in the Huang-Huai Region during Seed Germination

[Objective] To provide a theoretical foundation and germplasm resources for low-temperature-germination cotton breeding, the germination characteristics of 38 cotton varieties novel to or formerly widely planted in the Huang-Huai Region were evaluated under different low temperature stress conditions. [Method] Analysis of variance, the fuzzy membership function method, and cluster analysis were used to comprehensively evaluate the tolerance of these varieties to low temperature stress. [Result] As the temperature was lowered, germination rate, germination index, and vigor index exhibited a decreasing trend in all cotton varieties, but resistance to low temperature was significantly different among varieties. Cluster analysis divided the 38 varieties into three categories: highly resistant, resistant, and non-resistant. [Conclusion] Early-introduced varieties and those bred from early-introduced germplasm resources had weaker resistance to low temperature stress, with Stoneville and Deltapine series showing the lowest tolerance. The new transgenic insect-resistant cotton varieties SCRC 37 and SCRC 36 had the strongest resistance to low temperature stress.     

Effects of Exogenous 24-epibrassinolide on Photosynthetic Physiology of CottonSeedlings under Low Temperature

[Objective] The objective of this study was to investigate the effects of exogenous 24-epibrassinolide (EBR) on the photosynthetic physiology of cotton seedlings under low temperature and to provide basis for improving the cold tolerance of cotton by using EBR as growth regulator. [Method] Taking CCRI 60, Lumianyan 28 and Simian 3 as materials, a field experiment was carried out in Institute of Cotton Research of CAAS(Anyang county, Henan province). Before the first low temperature treatment, the cotton seedlings were sprayed with distilled water (Control) and different concentrations of EBR (0.1 mg·L^－1 and 0.2 mg·L^－1), respectively. After 3 days, the relative electrical conductivity, chlorophyll content, rapid chlorophyll fluorescence induction kinetic curve (OJIP) and fluorescence parameters were measured. [Result] Under low temperature, the relative conductivity of CCRI 60, Lumianyan 28 and Simian 3 spraying with EBR decreased by 17.7%～32.8% compared with control, and there was no significant difference between CCRI 60 and Lumianyan 28 in different concentrations of EBR treatments, butthe relative conductivity of Simian 3 treating with 0.2 mg·L^－1 EBR was significantly lower than those treatments with 0.1 mg·L^－1 EBR . The chl a and chl b contents increased by 9.7%～32.6% and 15.0%～18.9%, respectively. The maximum photochemical efficiency of photosystemⅡ (F_v/F_M) and photosynthetic performance index on absorption basis(PI_ABS) increased significantly. PI_ABS of CCRI 60 increase the maximum by 75.6% using 0.1 mg·L^－1 EBR. Lumianyan 28 and Simian 3 increased the maximum by 101.1% and 265.6% using 0.2 mg·L^－1 EBR, respectively; Absorbed photon flux per cross section (ABS/CSm), electron transport flux (further than QA) per active reactive center (ETo/RC) and probability for electron transport (φEo) are significantly increased. [Conclusion] Exogenous EBR can enhance the ability of low temperature tolerance of cotton seedlings and alleviate the inhibition of photosynthesis in cotton at low temperature. The study showed that 0.1 mg·L^－1 EBR performs well in CCRI 60 and 0.2 mg·L^－1 in Lumianyan 28 and Simian 3.     

不同氮水平处理下滴灌棉花ABA与10cm土层田间持水率之间的响应特征

为了揭示滴灌棉花节水节肥效果,为滴灌棉花节水节肥提供技术参数和理论依据,以‘新陆早42号’为试验材料,采用滴灌盆栽试验,研究滴灌棉花ABA与土层10 cm田间持水率之间的响应关系,获得蕾期和花铃期不同施N水平条件下其相关性及模型。研究结果表明:棉花蕾期不同处理纯N分别为2、4、6 g/盆的条件下,ABA含量与土层10 cm田间持水率之间呈负相关关系,相关性系数分别为-0.988、-0.894、-0.980,其模型分别为指数函数、对数函数和对数函数,模型拟合决定系数分别为0.954、0.796、0.946。花铃期,ABA含量与土层10 cm田间持水率之间呈负相关关系,相关性系数分别为-0.781、-0.600、-0.857,其模型分别为二次函数、二次函数和对数函数,模型拟合决定系数分别为0.623、0.911、0.965。本文研究的拟合模型函数有利地描述了滴灌棉花ABA与土层10 cm的田间持水率之间响应特性,可为内陆干旱区绿洲农业滴灌棉花的节水节肥的估算提供了新的计算方法和科学依据。     

山西花生地方品种芽期耐寒性鉴定及SSR遗传多样性

低温寒害是引起花生产量和品质下降的主要因素之一, 培育和种植高产稳产耐寒性强的品种是降低低温寒害的理想途径。然而高耐寒性种质的缺乏和耐寒性鉴定的困难, 是限制耐寒性育种取得突破的主要原因。本研究对72份山西花生地方品种进行芽期耐寒性鉴定, 以其相对发芽率和相对发芽指数作为耐寒性评价指标, 初步将其分为高耐寒、耐寒、中感、敏感、高感5级。为了解山西花生地方品种耐寒性遗传多样性, 合理、高效利用耐寒型花生资源, 用多态性好的90对SSR引物评价了不同耐寒性花生品种, 结果显示, 参试品种遗传多样性存在较大差异, 在遗传距离为0.4时, 被聚类为三大类群。3份高耐寒品种和7份耐寒品种分别聚类到不同的3个类群中, 说明耐寒性花生遗传多样性丰富。     

遥感干旱监测模型研究及在湖南夏季高温干旱中的应用

利用MODIS数据的增强型植被指数和陆地表面温度数据,反演得到湖南省逐月的改进型增强植被指数和温度状态指数,并与临近气象台站的综合气象干旱指数进行相关性分析,选取适宜的权重因子建立干旱状态指数(DCI)遥感干旱监测模型,并对其划分了遥感干旱等级。将此模型应用到2013 年6—9 月湖南旱情的监测中,该模型能较好地反映全省旱情的时空演变特征以及旱情的演变情况。该模型一定程度上削弱了云层的影响,在湿润的南方地区的农作物长势监测、作物估产和灾损评估等方面具有重要的应用前景。     

利用蒸发冷却空调开展控温储粮试验

在拱板式高大平房仓的拱板间安装蒸发冷却空调开展控温储粮技术,解决拱板间的积热,以达到延缓仓内温度和上层粮温上升速度的目的。蒸发冷却空调主要利用水泵抽取水槽内的水,通过分水器均匀分布到特殊纤维制成的湿帘组件上,而大流量轴流风机的转动令仓外空气以极高速度穿过湿帘组件将湿气散发到空间,以增加空气中的湿度,通过正压促使空气流动,从而达到换气降温的效果。试验结果表明,利用低功率蒸发冷却空调,可以有效排除拱板间的积热,实现换气降温、节能、环保、绿色储粮的目的。     

木板壁民居对湿热气候的适应性

为调查山地木板壁民居对重庆夏季湿热气候的适应性,选取当地典型木板壁民居作为研究对象,在夏季对其室内热环境进行实测。结合当地建筑特点及居民生活习惯,对实测数据进行分析,并利用APMV对室内热环境进行评价。结果表明,木板壁民居夏季依靠自然通风显著改善了室内热舒适度,夏季典型日APMV达Ⅱ级以上的约占65%。传统木夹壁民居在热环境营造上响应了当地气候特点,具有较好的气候适应性。     

稻谷玻璃化转变温度的测定方法及影响因素研究进展

对可测量稻谷玻璃化转变的方法进行了比较分析。简述了稻谷在干燥缓苏过程中影响玻璃化转变的主要因素:温度梯度和水分梯度。在不同的水分梯度稻谷各部位发生玻璃化转变的情况不同,稻谷表面含水量较低,易发生玻璃化转变;而稻谷内部则处于橡胶态,从而产生不同的内应力使稻谷产生裂纹,降低整精米率(HRY)。