二硫氰基甲烷对番茄苗安全性及其对根结线虫的防效

离体毒力测定表明，二硫氰基甲烷对根结线虫（Meloidogyne spp．）2龄幼虫EC50及EC95分别为0．720、1．663mg／L。温室试验表明76mg／L二硫氰基甲烷土壤处理，对间隔7、9d移栽的6周龄番茄苗安全。38、63mg／L药剂对番茄根结线虫的防治效果在30d和60d时分别达65．20％、86．94％和41．53％、46．15％；对土壤线虫的抑制在30d和50d时分别达58．57％、77．33％和38．22％、61．45％，各处理差异显著。     

Effects of various mixtures of ferulic acid and some of its microbial metabolic products on cucumber leaf expansion and dry matter in nutrient culture

Cucumber seedlings (Cucumis sativus cv. Early Green Cluster) ranging from 6 to 16 days of age were treated with various concentrations (0– 1 mM) of caffeic, ferulic,p-coumaric,p-hydroxybenzoic, protocatechuic, sinapic, syringic, and vanillic acids and mixtures of ferulic acid and one or two of the other phenolic acids. Seedlings were grown in full-strength Hoagland's solution which was changed every other day. Phenolic acid treatments were given with each nutrient solution change starting at day 6 or given once when seedlings were 13 or 14 days old. Leaf area, mean relative rates of leaf expansion, transpiration rates, water utilization, and the concentrations of the phenolic acids in nutrient solution were determined at one- or two-day intervals. Seedling dry weight was determined at final harvest. Seedling leaf area and dry weight were linearly related. Since leaf areas can be easily obtained without destructive sampling and leaf area expansion responds rapidly to phenolic acid treatments, it was utilized as the primary indicator of plant response. The resulting data suggested that a number of ferulic acid microbial metabolic products, as well as two other phenolic acids observed in soils (p-coumaric and syringic acid), can reduce seedling dry weight, leaf expansion, and water utilization of cucumber seedlings in a similar manner. The magnitude of impact of each of the phenolic acids, however, varied with phenolic acid and concentration. It appears that the inhibitory activity of these phenolic acids involved water relations of cucumber seedlings, since the phenolic acid treatments resulted in closure of stomata which then remained closed for several days after treatment. The data also demonstrated that the effects of mixtures of phenolic acids on cucumber seedlings may be synergistic, additive, or antagonistic. The type of response observed appeared to be related to the factor measured, the compounds in the nmixture, and the magnitued of inhibition associated with each compounds. The data also indicated that the effects of the various phenolic acids were reversible, since seedling leaf area increased rapidly once phenolic acids were removed from the root environment. Mean relative rates of leaf expansion recovered even in the presence of the various phenolic acids.Paper No. 9396 of the Journal Series of the North Carolina Agricultural Research Service. Raleigh, North Carolina. Mention of a trademark or proprietary product does not constitute a guarantee or warranty of the product by the Agricultural Research Service and does not imply its approval to the exclusion of other products that may be suitable.     

水杨酸处理对南瓜幼苗壮苗和抗寒能力的影响

以不同浓度水杨酸（SA）处理的南瓜幼苗,其中250 mg/L SA处理差异显著。从形态指标上表明SA处理可促进南瓜壮苗的形成。同时研究了4,15℃2种低温胁迫条件下最佳浓度水杨酸处理与25℃处理作为对照的南瓜幼苗抗寒性指标的变化。结果表明：经SA处理的脯氨酸、丙二醛与对照的差异极显著,外源SA能抑制脯氨酸的形成积累,且能提高南瓜幼苗叶片细胞膜的稳定性,抑制MDA形成积累。因此外源水杨酸能显著提高南瓜的抗寒性。     

The Distribution of Pyrimidinone Glucosides in Developing Seedlings of Vicia faba and Vicia narbonensis

The distribution of the pyrimidinone glucopyranosides vicine and convicine was investigated in resting seed and axenic developing seedlings up to 17 days of age in Vicia faba cv Troy, a low seed pyrimidinone glucopyranoside mutant (MTG5) derived from Troy, and a related species V narbonensis. The lower amounts of total vicine and convicine in resting seed of MTG5 were due primarily to a reduction in cotyledon pyrimidinone glucopyranosides, with the amount in the embryo axis much less affected. Distribution within developing seedlings revealed consistent patterns. A pulse of vicine appeared in both species in stems and roots at day 4 to day 7, then declined. Amounts of convicine rose initially then declined in seedling stems of both species, whereas in roots the rise in convicine continued throughout the period. The rise in convicine in the roots of V narbonensis could not have been accounted for by conversion from reserves of vicine. The low pyrimidinone glucopyranoside mutant MTG5 had less vicine initially in stems and roots than both Troy and V. narbonensis but by 17 days this had risen close to the levels of Troy and exceeded those of V narbonensis. By flowering, amounts of vicine and convicine in glass-house grown plants were similar in MTG5 and Troy. The levels of both compounds in the roots of MTG5 exceeded those of the sown seed. Consequently, both V faba and V narbonensis have the capacity to synthesise vicine and convicine in young plants. A mutation in a gene controlling levels of pyrimidinone glucopyranosides in the developing seed of V faba does not suppress the biosynthetic ability of young plants.     

热风干燥温度对南瓜子种子活力的影响

目的探究热风干燥对南瓜子活力的影响,得到可推广的南瓜热风干燥温度参数,为种子干燥加工提供参考。方法选用新鲜南瓜种子作为实验材料,设置自然阴干,以及30,35,40,45,50,55,60℃等8种不同干燥温度(±1℃),在4℃下保存30 d后测定其发芽率和发芽势,用丙二醛含量和超氧化物歧化酶活性以及幼苗的发育状况等指标表征南瓜子活力。结果最终确定适合南瓜子的干燥温度为55℃,此条件下南瓜种子的发芽率最高,为71%,发芽势为28%,丙二醛含量和超氧化物歧化酶活性均最低,种苗和根系发育的综合指数较高。结论55℃热风干燥温度可以较好地保留南瓜子活力,该温度下南瓜子老化损伤在研究范围内最小。     

干旱胁迫下外源ALA对烤烟幼苗光合特性和抗氧化能力的影响

为进一步探究外源5-氨基乙酰丙酸（ALA）对干旱胁迫下烟草幼苗抗旱能力的作用机理,以烤烟品种豫烟10号幼苗为试验材料,采用营养液培养的方法,研究叶面喷施不同浓度的（0~80 mg/L）外源ALA对干旱胁迫下烤烟幼苗烤烟光合特性和抗氧化能力的影响。结果表明干旱胁迫下烤烟叶片细胞活性氧和硫代巴比妥酸（TBARS）含量增加,叶绿体遭到破坏,光合速率降低,植物生长受到抑制。干旱胁迫下外源ALA能够显著降低烤烟叶片活性氧水平,提高抗氧化酶活性,以喷施20 mg/L ALA效果最为显著。其中与PEG处理相比,净光合速率（P_n）、蒸腾速率（T_r）、气孔导度（G_s）分别提高96.19%、96.79%和132.43%,抗氧化物酶（SOD、POD、CAT、APX）活性分别提高49.05%,61.97%,64.17%和70.08%。喷施适宜浓度的外源ALA可有效提高烤烟叶片光合特性和抗氧化能力,缓解活性氧伤害,从而增强烤烟幼苗对干旱胁迫的适应能力。     

Effects of Rice Straw Steam-explosion Spent Liquor on the Growth of Cabbage Seedlings

The direct use of spent liquor from pulping and papermaking engineering, which is abundant in active organic matter, can avoid resource wastage and environmental pollution. In this study, the effects of soaking solution and filtrate from steam-exploded rice straw on seed germination and the early development of cabbage were investigated. The results have shown that soaking solution and filtrate stimulated early cabbage growth at low concentrations. Optimal germination potential and the rate of soaking solution-treated cabbage seeds increased by 8% and 5%, respectively; meanwhile, that of the filtrate-treated cabbage seeds increased by 11% and 5%, respectively. Promotion of root growth by steam-exploded rice straw spent liquor was expressed in lateral root multiplication. The fresh weight of cabbage seedlings treated with the soaking solution/filtrate increased by more than 50% and the dry weight over 20%. Comparatively, the stimulation of filtrate on seed germination and early development of cabbage is superior to that of the soaking solution. Steam-exploded rice straw spent liquor is rich in bioactive lignin and oligosaccharides, which makes it a promising biostimulant for promoting crop growth.     

甜菜纸筒育苗应用底纸的试验简报

本文报道了甜菜纸筒育苗应用底纸的试验结果。采用日本产和国产两种底纸。育苗底纸对种子发芽和出苗无影响,可以促进主根的发育和培养壮苗。移栽后缓苗速度快、成活率高。对甜菜的后期生长发育和增产增糖有一定的促进作用。国产底纸可以代替日本底纸,这项技术可与纸筒育苗移栽技术配套使用。     

不同火土灰用量对烟苗生长发育的影响

为明确火土灰对烟苗生长发育的影响,采用漂浮育苗的方式,研究不同含量火土灰育苗基质对烟苗叶绿素含量、根系构型、根系活力及硝酸还原酶活性的影响。结果表明,随育苗基质中火土灰比例升高烟苗叶绿素含量、总根长、根总表面积、根平均直径、根体积和根系活力呈现先升高后降低趋势,在50%火土灰+50%常规育苗基质处理条件下达到峰值;根系硝酸还原酶活性随基质中火土灰用量增加呈增加趋势;育苗基质中火土灰用量在50%以内时,火土灰用量与总根长、根总表面积极显著正相关,与根总体积显著正相关。可见,50%的火土灰和50%的常规育苗基质配比最有助于促进烟苗生长发育。     

汾河灌区水稻节水灌溉技术研究

随着汾河水库调蓄能力的下降，加之工业挤占农业用水，汾河灌区灌溉水源日趋紧张。但汾河一坝灌区内的稻田仍采用传统的种植、灌溉模式、灌溉用水量最高达３万ｍ＾３／ｈｍ＾２，浪费水现象很严重。而且还存在着水稻与小麦灌溉用水的矛盾。为此，我们对水稻节水灌溉技术进行了试验研究，结果表明，新的栽培、灌溉技术旱育秧、旱整地、浅湿间歇灌溉比传统的水育秧、水整地、深水灌溉有明显的节水、增产效果。旱育秧比水育秧多栽６．７