Influence of Water Stress on the Chemical Composition of Seeds of Two Lupins (Lupinus albus and Lupinus mutabilis)

We have performed chemical proximate analysis and determined the carbohydrate profile of mature seeds of Lupinus albus, cv. Rio Maior and Lupinus mutabilis, cv. Potosi plants, either well watered (ww) or subjected to a water-stress period (imposed from the 15th to 35th day after anthesis). Protein content from lupin seeds was 450 and 320 g kg⁻¹ of seed on dry weight basis, for ww plants, respectively, of L. albus and L. mutabilis. Water stress did not affect protein content. The oil content of ww plants was about 120 g kg⁻¹ of seed dry weight for L. albus and 180 g kg⁻¹ of seed dry weight for L. mutabilis. Water stress reduced those values of half. The sugar content was about 90 g kg⁻¹ for L. albus and 50 g kg⁻¹ of seed dry weight for L. mutabilis, in ww plants. Water stress led to an increase in sugar content to 200 and 130 g kg⁻¹ of seed dry weight, respectively, for L. albus and L. mutabilis. The α-galactosides amounted to 70 % of the total sugars (raffinose being 30 % and stachyose, 40 %) and sucrose was about 20 % of the total sugars. Water stress increased total carbohydrates and increased the sucrose/α-galactoside ratio, although reducing raffinose content and increasing sucrose content.     

干草原牧草贮藏碳水化合物含量变化规律的研究

１９９３年在内蒙古正蓝旗于草原对１０种牧草贮藏碳水化合物含量的变化规律进行了研究。在植物生长期内，每１５天采样一次，分析牧草茎基部和根部的总糖和还原糖含量。试验结果表明，牧草在返青时都要消耗贮藏碳水化合物，分蘖后开始积累贮藏碳水化合物，在拔节和抽穗时又要消耗贮藏碳水化合物，开花、结实后又积累贮藏碳水化合物。但有的牧草出现相反的情况。根据牧草贮藏碳水化合物含量变化的规律，作者对合理利用草地提出了一些意见和建议。     

不同碳水化合物结构组成日粮在徐淮白山羊消化道内降解利用的研究

[目的]研究不同SC/NSC比例日粮对徐淮白山羊消化道内碳水化合物消化率的影响。[方法]选取4只体况良好,体重(32±2.5)kg的徐淮白山羊,安装永久性瘤胃瘘管、十二指肠近端瘘管和回肠末端瘘管,采用4×4拉丁方试验设计,饲喂4种不同碳水化合物结构组成日粮,其结构性碳水化物与非结构性碳水化合物的比例(SC/NSC)分别为3.52(Ⅰ)、2.06(Ⅱ)、1.28(Ⅲ)和0.84(Ⅳ)。[结果]降低SC/NSC比例,可以一定程度上提高徐淮白山羊瘤胃内和肠道内干物质(DM)、有机质(OM)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)及淀粉的消化利用率。随着SC/NSC的比例降低,DM与OM消化率显著升高,其中Ⅳ组极显著高于Ⅰ组(P0.01);NDF消化率表现为先升高后降低,Ⅲ组极显著高于Ⅰ组(P0.01);ADF与淀粉在整个消化道的消化率也表现为先升高后降低的趋势,但ADF消化率各组间差异不显著,而Ⅰ和Ⅱ2组的淀粉消化率则显著高于Ⅲ组(P0.05),并极显著高于Ⅳ组(P0.01)。[结论]日粮SC/NSC为1.28时,可以提高徐淮白山羊能量利用效率。     

全生育期菊芋不同器官果聚糖积累分配特征研究

以“青芋2号”和“青芋3号”菊芋为试材,研究了整个生长周期内菊芋不同器官中以果聚糖为主的碳水化合物含量变化动态特征以及在各器官的分配情况.结果表明:苗期叶、茎中果聚糖含量和总量增加迅速,主要贮存在叶中;植株迅速生长期和块茎形成期叶、茎中果聚糖含量呈起伏变化;全株果聚糖积累总量呈持续上升趋势,主要贮存在叶和茎中;开花期叶、茎中的果聚糖含量和积累总量先后达到全生育期的最高值,并完成果聚糖从叶片向茎的转运;块茎内含量稳定,积累总量增加缓慢;果聚糖主要贮存在茎内;块茎膨大期,全株的果聚糖积累量增加缓慢,以植株内部转运为主,果聚糖开始迅速从茎向块茎分配,到生育期末,全株果聚糖70％分配到块茎.     

短期夜间低温对栽培番茄和野生番茄果实蔗糖代谢的影响

 在人工气候室内以低温敏感的栽培番茄（Solanum lycopersicon）‘Money Maker’和耐低温的野生番茄（S. habrochaites）‘LA1777’为试材,研究了短期（4 d）夜间15 ℃处理和9 ℃、6 ℃及其恢复处理对番茄果实糖含量和蔗糖代谢相关酶活性的变化。结果表明：6 ℃处理0.5 d,耐低温的番茄（‘LA1777’）果实中果糖和葡萄糖含量升高,低温敏感番茄（‘Money Maker’）果实中两种糖含量无显著变化。6 ℃处理‘Money Maker’中蔗糖和淀粉的含量显著降低,而‘LA1777’中含量提高。在恢复期,两种番茄的蔗糖含量均恢复到对照水平,6 ℃处理的葡萄糖和果糖未恢复到对照水平,而9 ℃与对照无显著差异。6 ℃处理降低两种番茄果实中转化酶和蔗糖合成酶（SS分解方向）的活性,无法恢复至对照水平,‘Money Maker’果实中SS合成方向的活性和蔗糖磷酸合成酶（SPS）活性提高,而‘LA1777’变化不显著。说明短期夜间低温条件下耐低温的番茄是通过提高果实中总的碳水化合物含量来适应低温胁迫的,而低温敏感的番茄则是降低果实中碳水化合物含量来响应低温。     

Effects of Drought and Shading on Non-structural Carbohydrate Stored in the Stem of Potato (Solanum tuberosum L.)

Abstract

Most studies on non-structural carbohydrate (NSC) are concentrated on the leaf and tuber, and little is known about NSC in the stem and its function. To test the hypothesis that NSC stored in stem contributes to stable tuber bulking under stress conditions, we grew plants in pots in a greenhouse under drought and shading conditions for 17 d during tuber bulking. Compared with the control, drought and shading significantly reduced leaf and stem dry weights (DW) and total NSC concentration in the main stem base. However, tuber DW increased by 77% in drought and by 46% in shading conditions relative to the control. The contributions of NSC loss in the stem to tuber DW increase in drought and shading conditions were 37% and 54%, respectively. This study suggests that NSC stored in the stem base is supplied to tuber under stress conditions to support tuber bulking.     

不同糖类物质对多异瓢虫捕食与飞行行为及能力的影响

【目的】评价不同糖类物质对多异瓢虫捕食能力和飞行能力的影响,为发挥多异瓢虫的控害效能提供理论依据。【方法】在补充不同糖类营养后,室内测定多异瓢虫成虫在不同棉蚜密度条件下的捕食量,通过室内飞行磨系统测定不同处理下多异瓢虫的各项飞行参数。【结果】补充不同糖类营养后多异瓢虫成虫对棉蚜4龄若虫的捕食功能反应属于Holling-Ⅱ型。补充糖类营养后,随猎物密度逐渐增加,多异瓢虫对猎物的捕食能力增加,搜寻能力逐渐下降,与清水处理相比,葡萄糖、蔗糖处理下多异瓢虫捕食能力和搜寻能力均有提高,雌成虫日最大捕食量分别可达675.68、757.58头,雄成虫日最大捕食量可达374.53、609.76头;补充葡萄糖、果糖、蔗糖、麦芽糖、棉子糖后多异瓢虫累计飞行时间及累计飞行距离均显著延长,雌成虫累计飞行时间分别为7.78、6.17、7.58、6.80和6.63 h,累计飞行距离分别为9.51、7.70、8.46、6.94、7.12 km,雄成虫累计飞行时间分别为4.69、4.99、5.17、5.09和5.20 h,累计飞行距离分别为4.53、5.41、5.28、4.72和5.52 km;多异瓢虫雌虫在补充葡萄...     

枫桦树枝和树根木质部非结构性碳水化合物的地区差异

以中国伏牛山脉木札岭和小兴安岭帽儿山2个区域的散孔材树种枫桦(Betula costata)为对象,研究落叶后树枝和树根木质部中非结构性碳水化合物(NSC)含量的地域差异。结果表明,帽儿山枫桦树根和树枝的可溶性糖与淀粉含量均>木札岭;2个区域枫桦树根的可溶性糖与淀粉含量均>树枝。枫桦非结构性碳水化合物的地区差异以及组织差异是树木在休眠期应对环境变化特别是温度变化的结果。     

Increasing pre‐acclimation temperature reduces the freezing tolerance of winter‐type faba bean (Vicia faba L.)

Autumn‐sown winter‐type faba bean (Vicia faba L.) has been shown to have a yield advantage over spring sowing. Still, adoption of this overwintered pulse crop remains limited in temperate locations, due to inadequate winter hardiness. This research sought to understand how the prevailing temperature during emergence and seedling development, that is pre‐acclimation, influences freezing tolerance. Seedlings grown under a controlled “warm” 17/12°C (day/night) pre‐acclimation environment were initially less freezing tolerant than those grown under a “cold” 12/5°C temperature treatment. Stem and particularly root tissues were primarily responsible for slower cold acclimation, and there was a genotype specific response of above‐ground tissues to pre‐acclimation treatment. Both above and below‐ground tissues should be tested across a range of pre‐acclimation temperatures when screening faba bean germplasm for freezing tolerance.     

Mechanisms associated with tiller suppression under stagnant flooding in rice

Stagnant flooding (SF) during vegetative growth triggers stem elongation usually at the cost of tiller production in rice, reducing grain yield. To explore physiological mechanisms associated with tillering suppression under SF, three contrasting genotypes (Swarna and Swarna‐Sub1, both sensitive and IRRI154, tolerant) were evaluated under standing water depths of 0, 5, 30 and 50 cm. SF significantly suppressed tiller formation but increased plant height, root biomass, shoot elongation (ratio of plant height before and after flooding), leaf emergency and non‐structural carbohydrate (NSC) concentration (in root–shoot junction) in all genotypes at the early stage of development. Chlorophyll concentration in the upper leaves (upper most fully expanded leaf at top) was higher than in lower leaves (lowest green leaf at base), but decreased under SF in both. SF increased hydrogen peroxide (H₂O₂) at the early stage of treatment, with concomitant increase in malondialdehyde (MDA) production by stems and leaves. MDA concentration in root–shoot junction increased but delayed. Tiller number correlated negatively with plant height, shoot elongation, leaf emergency, MDA concentration in leaves and root–shoot junction, root biomass, and NSC concentration in the root–shoot junction. The results suggested existence of compensatory mechanisms between tiller growth and shoot elongation in rice for resilience under SF, where energy is mainly diverted for shoot elongation to escape flooding. The SF‐tolerant genotype produced less H₂O₂ and maintained energy balance for higher survival and better growth under stagnant flooding.