大豆豆荚与叶片超微结构的比较

以大豆品种东农42为试验材料,对其R4～R6期的叶片和豆荚的叶绿素含量及叶绿体超微结构进行了比较研究。电镜观察表明,叶片的叶肉细胞具有明显的栅栏组织和海绵组织,而豆荚作为叶片的同源器官其同化组织则无此明显区分。豆荚同化细胞的细胞壁厚,细胞排列呈梭形交错,细胞间隙小,有较多的胞间连丝,豆荚细胞中的叶绿体数量较叶肉细胞中的叶绿体少。R4的初期,淀粉粒较少,类囊体片层数量较多,但主要以基质片层纵向贯穿于叶绿体中;R5～R6期,豆荚的类囊体垛叠成基粒较明显,且淀粉粒逐渐增多;R6期,豆荚和叶片的叶绿体内都有数量不等的嗜锇小球积累。豆荚的叶绿体繁殖是独立于细胞分裂的现有叶绿体二分裂产生(哑铃状分裂)。叶绿素含量测定表明,豆荚叶绿素含量较叶片叶绿素含量低,这主要是与豆荚的叶绿体数量少有关。     

不同花生品种对花生果腐病的抗性鉴定

采用自然病圃鉴定法,对76个花生品种（系）进行了花生果腐病抗性评价,以期为抗病育种及田间病害防 治提供理论依据和抗性材料。结果表明,不同花生品种间对花生果腐病的抗性存在着显著差异,供试76份花生品 种（系）中未发现对果腐病免疫的品种,获得高抗品种2个,抗病品种7个,中抗品种12个,感病品种21个,高感品种 33个。聚类分析结果表明,分支I中的9个品种（尤其是花育9115）抗性较好,可进一步加以利用。花生对果腐病的 抗感性与荚果鲜重之间不存在显著相关。     

花生荚果发育及其调控研究进展

花生是重要的油料与经济作物,在农业种植业结构调整中发挥重要作用。荚果是花生的收获器官,深入 研究花生荚果发育及其调控,可以为高产育种提供理论依据。本文从花生荚果发育过程和内外限制因素的调控作 用,并结合激素、营养元素、遗传学研究以及DNA、RNA等分子调控机制,综述了近年来花生荚果发育相关的研究进 展,为后续研究提供参考。     

Shortening the generation cycle in faba bean (Vicia faba) by application of cytokinin and cold stress to assist speed breeding

The aim of this study was to reduce the length of the breeding cycle for faba bean by accelerating seed setting. We examined the mode and time of exogenous 6-benzylaminopurine (BAP) (cytokinin) application, and cold treatments and their combinations in two faba bean genotypes. Acropetal node number of pod and seed set and pollen viability were recorded during the experiments. Application of BAP improved pollen germination. The application of 10^–5 M BAP 4 days after flowering increased seed set at the lower nodes. Cold treatment (8/4°C day/night for 2 days) after the onset of flowering induced the formation of more pods and faster pod set compared to the non-cold treatment. The time to first seed was significantly reduced, and pollen viability was increased in plants exposed to cold treatment. Increased pollen viability also showed a significant positive correlation with seed setting. The combinations of 10^–5 BAP and cold treatment together had similar and independent effects. These results will accelerate plant breeding in faba bean by providing additional tools for reducing generation time.     

栽培密度对高产大豆根系生长及花荚形成的影响

为探明栽培密度对高产大豆根系生长和花荚形成的影响规律,田间试验设置21.0（D₁）、30.0（D₂）、48.0（D₃）×104株·hm^-2 3种栽培密度,研究了新大豆27号、新大豆8号在0~60 cm土层中根系生长、开花、结荚过程及产量的变化。结果表明,相对于D1,D2、D3密度下新大豆27号总根干重增加了23.68%、18.48%,总根长增加了9.33%、26.72%,新大豆8号总根干重增加了27.25%、19.71%,总根长增加了6.94%、30.80%,且增量以40~60 cm为主;增加至密度D₃时,新大豆27号开花和结荚高峰出现时间较D₁分别推迟了2、8 d,新大豆8号推迟了2、6 d,但二者单位面积的总花数、总荚数、总腔数和总粒数分别较D₁提高了51.92%、10.29%、7.66%、23.05%和49.47%、31.91%、35.40%、16.11%;总花数与始荚期根干重、根长度呈正相关关系,新大豆27号R²值分别为0.8477^*、0.9106^*,新大豆8号R²值分别为0.7531、0.9993^**;总腔数与始粒期根干重、根长度呈正相关关系,新大豆27号R²值分别为0.6954、0.9837^**,新大豆8号R²值分别为0.7902^*、0.9277^*;且根长度与总花数、总腔数的关系比根干重更密切。合理密植显著提高大豆籽粒产量,是密植促进了大豆根系生长,增加了单位面积总根长和深层根量,进而增加了单位面积花数、荚数、腔数和粒数的结果。     

广东雷州杂草稻sh4和qSH1基因的功能SNP位点序列分析

sh4和qSH1基因是水稻的主效落粒基因,本研究旨在测定雷州杂草稻的sh4和qSH1的基因型,为雷州杂草稻的落粒机制研究提供分子基础。本研究从雷州10个杂草稻群体采集了100个单株及10份栽培稻种子,观测其颖壳颜色、果皮颜色和芒及落粒率,并对sh4和qSH1的功能SNP位点进行PCR扩增及序列分析。结果表明,57份杂草稻的sh4功能SNP位点为野生落粒型（G）,15份为杂合型G/T,28份为突变难落粒型（T）。其中,G型和G/T型的72份杂草稻的落粒率都极高（95%~100%）,而28份T型杂草稻中,19份为中度落粒（30%~75%）,5份杂草稻的落粒率很高（>95%）,4份杂草稻的落粒率小于30%。100份杂草稻和10份栽培稻的qSH1功能SNP位点均为G。结合落粒表型及基因型,推测sh4是调控雷州杂草稻落粒性的一个主要基因。     

海南省可可黑果病病原鉴定及其发生规律

采用形态特征鉴定及rDNA-ITS序列分析相结合的方法,对海南可可黑果病病原进行鉴定,并通过定点连续调查研究该病在海南的发生规律。结果表明,该病病原为柑橘褐腐疫霉(Phytophthora citrophthora)。降雨量对该病的发生有着显著的影响,在海南发病高峰期一般在9~11月份。     

菜豆金黄荚色产生的生化机制研究

选用菜豆金黄色豆荚品种‘A18’和绿色豆荚品种‘热那亚’为试验材料,通过测定豆荚发育过程中荚壁的叶绿素、类胡萝卜素和叶绿素合成途径中相关代谢物质含量,探讨菜豆金黄荚色的形成机理。结果表明,嫩荚呈现金黄色是由于叶绿素缺乏,推测是因为叶绿素酸酯a(chlorophyllide a)的合成受阻导致;利用荧光定量PCR对叶绿素生物合成相关基因的表达进行分析,发现在‘A18’中CHLM和DVR的表达量从花后12 d开始下降,但CHLP、CHLG和CAO的表达量在多个时间点高于‘热那亚’,这说明虽然叶绿素酸酯a合成受阻,但叶绿素的合成仍然能进行。     

Effects during Period of Siliqua Developing of KH2PO4 and MgSO4 Application on Nitrogen Transportation in Pods of Oilseed Rape(Brassica napus L.)

An experiment was conducted in field experiment plot to investigate nitrogen transportation from hulls of pods in different periods at early stage of siliqua developing and effect of KH₂PO₄ and MgSO₄ application on it using ¹⁵N-urea.
More than 80 % of ¹⁵N applied on the surface of pods at lower terminal during flowering was recovered from all pods one month after flowering, most of them were still in the hulls of labelled pods, 17-27 % of ^l5N applied was transported into seeds, a small amount was transported to pods at upper terminal, a little amount was found in pods at branch. More ^l5N applied in middle period of flowering was transported to pods at upper terminal and branch than those applied in early period of flowering. It should be further investigated to conclude how will be going on transportation of nitrogen from hulls as preceding of siliqua developing towards maturity of seeds and its difference between ¹⁵N applied in more different periods.
Application of KH₂PO₄ and MgSO₄ with ¹⁵N-urea of surface of pods promoted transportation of ¹⁵N into seeds from hulls, effect of MgSO₄ was more notable.     

Flowering, Pod Set and Reproductive Success in Soya Bean

Much of the variation in yield of soya bean [Glycine max (L.) Merrill] and other grain crops is associated with changes in the number of pods and seeds per unit area. Photosynthesis and seed characteristics are the primary determinants of pod and seed number, but recent research suggests that the temporal distribution of flower production may also play an important role. Soya bean has a long flowering period (up to 40 days or more), but most of the flowers are produced in a much shorter time. The length of the period varies among cultivars, growth habits (indeterminate and determinate) and environments. The reproductive success of flowers produced early in the period is usually greater than those produced later. Little is known, however, of the regulation of the temporal distribution of flower production or its potential role in determining pod and seed number at maturity. Research is needed to determine first, if the temporal distribution can be manipulated to increase pod and seed set and secondly, if such increases would result in higher yields.