羊草＋杂类草群落生物量动态模式的研究

对黑龙江肇州县羊草＋杂类草群落地上生物量的季节动态、地下生物量的分布以及地上生物量与降雨量、温度之间的关系进行了分析．结果表明，在生长季内，群落地上生物量动态模式呈单峰型，符合四次多项式模型增长，最大地上生物量出现在８月５日，其值为１９７．３ｍ２而后下降；群落地下生物量分布由上至下呈负幂函数变化，其模型为：Ｂｕ＝Ｙ·（Ｄ＋１０）－ｘ．其中在０－３０ｃｍ土层中，群落地下生物量占总地下生物量的７７％～８２％．     

微生物诱导剂浸种对小麦萌发期的抗旱诱导效果

试验结果表明,在正常供水和水分胁迫条件下,经微生物诱导剂处理,可增加小麦萌发时期的根冠比,而且在水分胁迫条件下的增加幅度大于正常供水条件。微生物诱导剂可在水分胁迫条件下促进根系生长发育,提高根系干物质积累。这些性状的改善有利于提高小麦的抗旱能力。但诱导剂处理后在一定程度上抑制了小麦种子萌发率以及小麦芽和根的伸长生长。     

N_(98s)×特青(亚种间杂交稻)抽穗后物质生产及分配特点研究初报

对N×特青示范田中试区与肥料试验田各处理小区稻株分析结果表明:抽穗后,亚种间杂交稻N×特青比常规稻特青干物质生产能力强,灌浆速度快;地上部各器官占植株干重比例,前者叶片比重大于茎,后者茎比重大于叶。亚种间杂交稻对肥料反应敏感,抽穗后,干物质累积,植株高度,每穗总粒数和粒重均随施肥量增加而增加,在高肥区有利于进一步提高产量,但增施氮肥后,灌浆速度明显滞后。     

Effect of Nitrogen Rate and Stubble Height on Dry Matter Yield,Crude Protein Content and Crude Protein Yield of a Sorghum–Sudangrass Hybrid[Sorghum bicolor (L.) Moench × Sorghum sudanense (Piper) Stapf.] in the Three‐Cutting System

In this study, the effects of nitrogen (N) rate (60, 120, 180 and 240 kg N ha^?1 applied in three equal dressings at seeding and after the first and second cuttings) and stubble height (7, 14 and 21 cm) on the dry matter (DM) yield, crude protein (CP) content, and CP yield of a sorghum–sudangrass hybrid [Sorghum bicolor (L.) Moench × Sorghum sudanense (Piper) Stapf., cv. Pioneer 988] in the three‐cut system was investigated. The N rate had no significant effect in the first and third cuttings, but in the second cutting DM yields increased significantly with increase in N rate. The highest yield of 9.1 t ha^?1 was obtained with 80 kg N ha^?1 for the average of 2 years at the second cutting, but no significant difference was found among the 40, 60 and 80 kg N ha^?1 rates. CP content and yield were not significantly affected by N rate at the first and third cuttings, but CP content and yield were significantly affected by application of N at the second cutting. Stubble height had a significant effect on CP content at the third cutting. However, it had no significant effect on CP content at the first and second cuttings. Stubble height had a significant effect on the CP yield at the first cutting, but no significant effect on CP yield at the second and third cuttings.     

毛条灌木草场建立方法的研究

通过对毛条灌木林进行平茬，在人工灌溉条件下观测平茬毛条生物产量的变化，认为毛条平茬后具有很强的萌蘖能力，可产生原生枝条数4．1倍的萌生枝条；每年灌溉1次，灌水量1050m^3／hm^2，既可维持平茬毛条林的正常生长；在4株／m^2的密度条件下，平茬毛条的年产草量(干质量)可达538g／m^2，植被盖度可达78％以上，达到了经济效益和生态效益的共同提高；根据平茬毛条的生长变化规律，可初步确定冬春季节和夏季干旱时期为毛条灌木草场适宜的放牧时间。     

Analysis of Growth and Productivity of Indian Mustard (Brassica juncea) in Relation to FYM, Nitrogen and Source of Fertilizer

A field experiment was conducted during the winter seasons of 1992–93 and 1993–94 at Anand to study the effect of FYM, nitrogen and source of fertilizer on growth and yield of mustard [ Brassica juncea (L.) Czernj & Cosson]. The results showed significant variation in leaf area index (LAI), crop growth rate (CGR), dry matter production and seed yield. The direct effect of farmyard manure (FYM) was conspicuous in improving the growth of mustard. FYM application at 10 tonnes ha⁻¹ significantly increased the LAI, CGR and dry matter accumulation per plant at almost all the stages during first year study (1992–93) and in pooled analysis. Similarly, nitrogen application registered maximum LAI, CGR at 75 kg level and RGR and NAR at 50 kg level at almost all the during both years. Sulphur carrying source (Ammonium sulphate plus single super phosphate) increased all stages growth characters. Maximum dry matter accumulation per plant and seed yield were recorded with highest levels of FYM (20 tonnes ha⁻¹), N (75 kg ha⁻¹) and source having S. Seed yield was strongly associated with LAI and dry matter accumulation per plant at all the stages.     

奥芬哒唑干混悬剂驱除猪蛔虫的效果观察

应用奥芬哒唑干混悬剂给猪口服驱虫，设5mg/kg b．w，l0mg/kg b．w，15mg／kg b．w3个剂量试验组和对照组。结果：5mg/kg剖量组的虫卵转阴率为60％，减少率为99．40％；l0mg/kg和15mg/kg剂量组虫卵转阴率和减少率均达100%。全部给药猪均未出现毒副反应。     

松嫩平原羊草草地水淹干扰恢复过程的群落动态

根据随机取样的测定数据，经过幂函数和多元回归分析及相关检验，揭示了草地水淹干扰对羊草 寸草苔、羊草 杂类草群范数量性状的变化规律。水淹干扰对草地植被的物种组成及其比例有明显的影响。水淹后基本恢复到正常草地的种类数量和生产量配置大约需要6—7年。随着生境水分减少和土壤变干，羊草种群的数量和生物量均以幂函数形式增加，而寸草苔和杂类草的数量和生物量则呈先增后降的变化过程。     

铅对草坪植物生物量与叶绿素水平的影响

通过盆载模拟试验研究了铅对植物生物量、叶片叶缘素含量变化的影响，以及植物中毒后的症状。结果表明，铅对植物根系生长发育影响极大，可使根冠细胞有丝分裂减少、根量减少。铅进入叶肉组织后导致叶片失绿，严重时使叶片枯黄死亡。试验早期植物中毒症状表现为根冠膨大变黑，严重时根系腐烂。当营养液中Pb浓度达5.0mol／m^3时，试验后期引起植物死亡且不易恢复。     

1年生樟子松苗营养积累过程的研究

通过 3a对樟子松 1年生苗木的营养积累过程的研究表明 :1年生樟子松苗在生长期内 ,干物质的积累和对N、P、K的吸收利用是以叶为中心 ,到生长中、后期 ,根、茎、叶中的干物质积累和对三元素的吸收积累速率明显加快。而在不同生长时期对三元素的吸收利用比例也不同 ,生长前期表现为N >P >K ,生长中后期表现为K >N >P ,生长后期表现为P >N >K。