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1.
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. 相似文献
2.
以200份玉米优良自交系为材料,2022-2023年夏分别进行小斑病菌的田间接种,综合两年数据共鉴定出高抗小斑病的玉米自交系3份,分别为K22、CML50和齐319;筛选到包括Mo17在内的抗性玉米自交系24份。选取K22和B73两个具有不同抗性水平的玉米自交系进行小斑病菌的室内接种。结果表明,48 h和72 h时,自交系K22叶片的病斑数、病斑面积和病斑面积比等各项指标均显著优于自交系B73,进一步验证田间鉴定的准确性。48 h或72 h时,高抗小斑病自交系K22与感病对照B73相比,5种防御酶活性增加14.32%~70.45%。 相似文献
3.
探明不同种类叶面肥对柑橘果实品质及产量的影响,为柑橘提质增效提供理论依据。以柑橘品种“宫川”为试材,设置喷施清水(CK)、磷酸二氢钾(T1)、奇茵(T2)及欧甘(T3)4个处理,比较分析各处理对柑橘果实品质及产量的影响。结果表明,不同水溶肥对果实的单果重、纵径、横径及净重差异不显著。喷施叶面肥后,T1、T2、T3的可溶性固形物含量和可滴定酸含量比CK有所增加,但差异不显著。T2的可溶性固形物含量和可滴定酸含量最高,分别为9.39%、0.75%,显著高于CK,可溶性固形物含量比CK提高了14.93%,可滴定酸含量比CK提高了19.05%。T2、T3、T1处理的单株挂果数分别比CK高31.59%、16.28%、4.46%;T2、T3、T1处理的每公顷产量分别比CK高12.96%、6.57%、3.00%。结论:喷施叶面肥能提高柑橘果实品质和产量,T2的综合效果更好。 相似文献
4.
采用田间随机区组试验设计方法结合数学统计分析方法,研究“云烟97”、“云烟121”、“秦烟96”、“NC71”4个烤烟品种烟叶产质量。结果表明:云烟121烟株农艺性状、烟叶外观质量、烟叶化学成分含量最好;4个烤烟品种各等级烟叶总氮含量偏低,总糖、还原糖含量均偏高,烟碱、氯、钾均在优质烟叶适宜范围。 相似文献
5.
以刨花润楠主要分布区的14个种源为研究对象,在广州增城开展种源试验,通过对14个种源的刨花润楠苗高、地径、叶面积、叶周长等性状进行观测,分析不同种源苗期性状的遗传变异规律。结果表明:3个生长性状种源间和种源内变异系数相当,其种源间和种源内生长性状变异均较丰富;8个叶片性状种源间的变异系数为17.52%~44.71%,不同种源间叶片性状亦变异明显;生长性状的种源遗传力均大于0.750,说明在一定程度上刨花润楠的苗高、地径等苗期生长性状受自身遗传控制,且不同种源间变异明显,种源选择潜力较大。刨花润楠苗期生长性状的地理及气候变异趋势不明显,表现出随机现象;苗木生长性状与叶片大小呈负相关,即叶片越大、叶柄越长,苗木生长有变慢的趋势;对种源苗期性状进行聚类,可将刨花润楠14个种源划分为5个类群;刨花润楠苗期生长及叶片性状有一定的地理趋势,但也有一定的随机性。以地径为标准对刨花润楠优良种源进行筛选,初步选出永春、兴安、昭平3个种源作为适宜广东地区造林的优势种源。 相似文献
6.
Altitude affects leaf stoichiometry by regulating temperature and precipitation, and influencing soil properties in mountain ecosystems. Leaf carbon concentration(C), leaf nitrogen concentration(N),leaf phosphorous concentration(P), and their stoichiometric ratios of Leontopodium lentopodioides(Willd.)Beauv., a widespread species in degraded grasslands, were investigated to explore its response and adaptation strategy to environmental changes along four altitude gradients(2500, 3000, 3500, and 3... 相似文献
7.
8.
以三色竹芋的侧芽为外植体,研究了三色竹芋不定芽诱导、增殖和生根的组织培养过程,并研究了6-BA浓度和继代次数对叶片颜色的影响。结果表明:以三色竹芋的侧芽为外植体,经过芽的分化、增殖和生根可获得批量组培苗;降低6-BA的浓度,减少继代次数,有利于保持叶片的颜色。 相似文献
9.
养蚕生产中家蚕的桑叶食下量难以人为控制在同一水平,通常认为食下量会对蚕体生长发育及全茧量等产茧量指标产生显著甚至极显著影响。以山东省现行的3个春用蚕品种为材料,将食下量作为协变量进行协方差分析的结果表明,3个家蚕品种在3-5龄的蚕体质量增量、全茧量、茧层量性状指标上无统计学意义(P>0.125 2),仅个别指标均值间的最大差异在0.1水平下显著(P全茧量=0.066 9,P茧层量=0.056 1),因此该方法校正了用常规方差分析得出的上述性状指标在品种间存在极显著差异(P<0.000 1)的有偏结论,还明确了消化吸收量对上述性状指标影响不显著,可不作为协变量考虑。 相似文献
10.
Objective To investigate the relationship of the iridocorneal angle as it appears on ultrasound biomicroscopy (UBM) to increases in IOP post-phacoemulsification in the canine eye.
Animals studied 47 eyes of 28 dogs of various age, sex, and breed.
Methods The ciliary process and limbus were used as a reference points to measure the angle opening distance (AOD), which was set by multiplying 0.45 by the distance between the ciliary process and limbus (when measured from the ciliary process). Pressure measurements were taken at five set points: Before, immediately post-, one day post-, 1 week post-, and 1 month post-phacoemulsification.
Results A weak relationship between the AOD and the IOP one day post-phacoemulsification (Intercept: 2.83, Slope: –1.24, P -value: 0.0155) was observed. No relationship immediately post-operative (Intercept: 3.45, Slope: –1.34, P -value: 0.0651), 1 week post-phacoemulsification (Intercept: 2.31, Slope: –0.01, P -value: 0.9829), 1 month post-phacoemulsification (Intercept: 1.85, Slope: –0.49, P -value: 0.1533) was observed. The pre-operative measurements made with UBM were: Distance from limbus to ciliary process (DLCP): (Minimum: 1.152, Maximum: 2.992, Mean: 1.91, SD: 0.468); AOD (Minimum: 0.104, Maximum: 0.764, Mean: 0.40, SD: 0.172).
Conclusions The relationship between AOD as measured by UBM pre-operatively is weakly associated with IOP pressure elevations at day one post-phacoemulsification. Further study is required prospectively to establish the importance of this relationship. Initial measurements of the canine iridocorneal angle were created, suggesting a method to be used in the future to establish true canine normal measurements. 相似文献
Animals studied 47 eyes of 28 dogs of various age, sex, and breed.
Methods The ciliary process and limbus were used as a reference points to measure the angle opening distance (AOD), which was set by multiplying 0.45 by the distance between the ciliary process and limbus (when measured from the ciliary process). Pressure measurements were taken at five set points: Before, immediately post-, one day post-, 1 week post-, and 1 month post-phacoemulsification.
Results A weak relationship between the AOD and the IOP one day post-phacoemulsification (Intercept: 2.83, Slope: –1.24, P -value: 0.0155) was observed. No relationship immediately post-operative (Intercept: 3.45, Slope: –1.34, P -value: 0.0651), 1 week post-phacoemulsification (Intercept: 2.31, Slope: –0.01, P -value: 0.9829), 1 month post-phacoemulsification (Intercept: 1.85, Slope: –0.49, P -value: 0.1533) was observed. The pre-operative measurements made with UBM were: Distance from limbus to ciliary process (DLCP): (Minimum: 1.152, Maximum: 2.992, Mean: 1.91, SD: 0.468); AOD (Minimum: 0.104, Maximum: 0.764, Mean: 0.40, SD: 0.172).
Conclusions The relationship between AOD as measured by UBM pre-operatively is weakly associated with IOP pressure elevations at day one post-phacoemulsification. Further study is required prospectively to establish the importance of this relationship. Initial measurements of the canine iridocorneal angle were created, suggesting a method to be used in the future to establish true canine normal measurements. 相似文献