不同龄期及不同长势核桃的养分特征

通过对核桃苗期、幼龄期、始果期的植株叶片和果实营养元素N、P、K和微量元素Fe、Zn含量的分析测试,结果表明,核桃1年生苗木叶片中N、P、K、Zn含量高于幼龄期和始果期植株;核桃各龄期在年生长过程中,叶片中的N、P、K、Fe、Zn养分含量总体呈下降趋势,但N素含量在第2次生长期7月较年生长初期低,比其它生长时期高,在年生长中N、P、K养分含量的比例存在差异,N、K素营养相对含量经历“低-高-低”的过程,N素营养相对含量表现尤其明显;核桃幼龄期、始果期植株长势的差异主要体现在同一时间叶片及果实中N含量的差异。     

起身期断根对冬小麦后期光合和生长的影响

通过盆栽小麦起身期断根试验,研究了断初生根和部分次生根对小麦后期光合和生长的影响。结果表明:断初生根和部分次生根,均降低了断根初期小麦光合速率,而促进后期光合速率;同时,断根降低了成熟期小麦根系干质量、地上部干质量以及产量;断初生根比断部分次生根对小麦的影响更明显。     

Microspore culture is successful in most crop types of Brassica oleracea L.

Summary Microspore culture was shown to be applicable to a broad range of accessions belonging to six horticulturally important crop types of Brassica oleracea: broccoli, white cabbage, cauliflower, savoy cabbage, Brussels sprouts and curly kale. Of 64 accessions tested 86% were responsive. Large genotypic differences were found in number of embryos produced per flower bud, and in frequency and mode of regeneration of plants from embryos. B. oleracea was characterized by a strong asynchrony of microspore development within single buds. Microspore populations optimal for culture contained a large proportion (10–40%) of binucleate pollen. An initial high temperature treatment was essential for microspore embryogenesis. Growth conditions of the donor plants during inflorescence formation were less critical.     

Sensitivity to Drought Stress of Three Soybean Cultivars During Different Growth Stages

Three soybean ( Glycine max L.) culivars, Lee-74, Wright , and Ra 401 , were subjected to 100 % (control), 75 %, and 50 % of field capacity during vegetative (VI), flowering (R2), and pod-filling (R4) stages in greenhouse and field studies. Stress applied at R2 significantly reduced the yield in the greenhouse, while in the field, the maximum reduction was observed when the plants were subjected to stress at R4. Stress during VI reduced the yield components less than stress applied during R2 or R4 stages in both studies. The pod number and seed weight were the yield components most affected by drought stress, and the number of seeds per pod the least affected. Yield stress index was significantly correlated with the yield and its components. The reproductive stage was clearly more sensitive to drought than the vegetative stage. The cultivar Lee 74 had the highest yield and the second highest yield stress index whereas the cultivar Ra 401 had the lowest yield.     

木薯后期衰老对淀粉积累的影响

对新选056、南洋红、GR891、辐选01、华南124和新选048六个木薯品种生育后期抗衰老生理和淀粉积累特性进行研究。结果表明:不同木薯品种生育后期抗衰老生理与淀粉积累特性有明显差异,木薯后期茎叶生长状况对块根淀粉积累有明显影响,后期茎叶过早衰老或生长过旺对块根淀粉积累都不利。对抗衰老能力最强的是华南124,其次是辐选01和新选048,抗衰老能力最弱的是南洋红。其中新选056、南洋红、GR891、辐选01、华南124和新选048生育后期叶片过氧化物酶活性分别为383.93△OD470/gFw.min,279.33△OD470/gFw.min,405.20△OD470/gFw.min,445.97△OD470/gFw.min,364.43△OD470/gFw.min和202.20△OD470/gFw.min;丙二醛含量分别为0.0178μmol/gFW,0.0189μmol/gFW,0.0237μmol/gFW,0.0153μmol/gFW,0.0128μmol/gFW和0.0140μmol/gFW;可溶性糖含量分别为0.74%,0.70%,1.02%,0.84%,1.12%和1.30%;自由水/束缚水比值分别为3.07,4.77,6.85,3.64,2.57和3.11;块根淀粉含量分别为29.6%,25.8%,32.8%,32.7%,25.6%和28.9%。     

Pleiotropic effect of the dwarfing gene d18-k on cool tolerance at booting stage under the genetic background of an extremely cool-tolerant line Norin-PL8 in rice

Norin‐PL8 (‘PL8’) is an extremely cool‐tolerant line of rice in Japan that contains genes for cool tolerance originating from a javanica landrace. It was investigated to see whether the dwarfing gene d18‐k (kotaketamanishiki dwarf) exerts its pleiotropic effect on enhancing the cool tolerance at the booting stage in the genetic background of PL8. The d18‐k isogenic line of the recurrent parent PL8 (D8), PL8, and two commercial cultivars ‘Hayayuki’ and ‘Kirara 397’ were used. For each line/cultivar, the 12°C‐5‐day treatment was conducted at various times during the booting stage. In addition to spikelet fertility, the ratio (%) of the fertilized‐spikelet number of each treated panicle to the varietal mean of fertilized‐spikelet number per panicle in the control (FS‐T/C) was adopted to estimate cool temperature damage. For FS‐T/C, the lines‐cultivars ranked in the order of D8 > PL8 > ‘Hayayuki’ > ‘Kirara 397’, reflecting their cool tolerances. D8 exceeded PL8 in both pollen grain number per anther in the control and as an indicator of pollen fertility after the treatment, as a result of the effects of d18‐k. Consequently, d18‐k can be used to develop super‐highly cool‐tolerant cultivars for cool‐weather areas.     

不同生育期干旱对冬小麦根冠生长发育的影响

用盆栽对冬小麦不同生育阶段进行不同程度水分调亏试验结果表明：拔节－孕穗期、抽穗－杨花期和灌浆－成熟3个阶段内土壤相对含水量（RW）上限为40％、50％、60％的水分亏缺均对作物的根冠发育产生了影响，拔节－孕穗期RW40％的水分亏缺处理使株高降低很多，低于不施肥的ck1，复水后也无法恢复。不同生育期的干旱均引起根冠干重的下降，根长则不同，水分亏缺有时会使根长增加，要看具体亏缺程度而定。根系不如冠部对干旱敏感，干旱促进营养物质向根的分配，减少了向冠部的运输，导致根冠比增大，另外，随生育期的推移，干旱对根冠比的影响减小。     

甜菜子叶期幼苗硝态氮吸收特性及其与硝酸还原酶活性的关系

６个有代表性的甜菜品种在人工气候室的营养液培养试验表明，甜菜子叶期幼苗对ＮＯ３＾－的吸收要经最初２ｈ的适应阶段后才可均匀进行。均匀吸收后，观察到多倍体的吸收量〉２倍体，倍性相同品种中Ｅ型〉ＮＥ型〉ＮＺ型〉Ｚ型的初步结果。不同类型品种间ＮＯ３＾－吸收的表观米氏常数（Ｋｍ，ａｐｐ）、最大吸收速率（Ｉｍ）有明显差异，除多倍体ＮＺ型品种甜研３０１的Ｋｍ，ａｐｐ较低而Ｉｍ较高外，其余品种的Ｋｍ，ａｐｐ和Ｉｍ     

人群阶段营养与食品加工

归纳了人体在不同生长阶段的营养原则及相应的阶段食品加工时的营养要求.     

绿豆种质资源苗期抗旱性鉴定

鉴定筛选苗期抗旱绿豆种质,对改良绿豆品种抗旱性、促进绿豆产业发展具有重要意义,同时,也为"绿豆抗旱性鉴定评价技术规范"的制定提供方法和信息支撑。本研究以70份绿豆种质为材料,采用苗期反复干旱法,测定幼苗存活率、萎蔫指数、株高、叶片鲜重、叶片干重、叶片含水量、生物量和胁迫指数等指标,分析各指标间的相关性,结果显示第1次旱胁迫后的幼苗存活率与第2次旱胁迫后的幼苗存活率呈极显著正相关;萎蔫指数、株高与幼苗存活率呈极显著负相关,故遴选出第1次旱胁迫幼苗存活率、萎蔫指数和株高为绿豆苗期抗旱性评价的适宜指标。采用隶属函数法,综合分析划级,获得高抗旱种质16份、抗旱种质20份,中抗种质23份、敏感种质8份和极敏感种质3份。以第1次旱胁迫幼苗存活率、萎蔫指数和胁迫株高分别评价绿豆的抗旱性并与综合评价结果相比较,一致率分别为70.0%、58.6%和51.4%。认为第1次旱胁迫幼苗存活率可以作为大规模绿豆种质苗期抗旱筛选的鉴定指标。