不同类型园林植物对环境因子的影响

通过在晴天和阴天2组对比试验,研究了木槿、栾树与杨树3种不同植物群落对环境中空气温度、空气湿度、光照强度、地温4个因子的影响作用.结果表明:在阴天类型中,3种植物群落均能有效地降低气温、地温与光照强度,从而提高空气湿度,且调节效果为:杨树＞栾树＞木槿;在晴天类型中,栾树与杨树群落的调节效果与阴天相似,其中杨树的调节效果大于栾树.此外,每种植物群落在晴天时对环境因子的调节效果大于阴天时的调节效果.     

皖北地区乡土秋色叶树种资源开发前景分析

采用实地调查与阅读文献相结合的方法,对皖北地区现有的29种乡土秋色叶树种资源种类、主要特征和分布情况进行实地调查与研究.结果表明:皖北地区乡土秋色叶树种资源丰富,主要分布于淮北、萧县、宿州、砀山及怀远等低山丘陵地区,且大多秋色叶景观综合表现优秀.并对其进行开发应用综合评价,进而从市场需求、苗木繁育、专类保护、风景林营造及特色产业培育等方面,对乡土秋色叶树种资源的开发前景进行深入分析.     

越橘新品种“禾韵1号”选育报告

“禾韵1号”是由美国引入的越橘中选出,属半高丛类型.果实中晚熟,在吉林地区7月下旬至8月上旬成熟,扁圆形,被白色果粉,呈蓝色,平均单果质量1.96 g,品质佳.结果枝条上呈串状结果,果穗紧密.抗病力和抗寒力强,丰产性好.适宜于吉林省土壤pH4.5～5.5、冬季绝对低温不低于-35℃(简易防寒)、无霜期110 d以上、≥10℃年有效积温2 300℃以上的地区引种试栽.     

低温弱光对西葫芦叶片解剖结构的影响

研究了不同温度和光照条件对西葫芦幼苗叶片解剖结构的影响。研究结果表明,低温弱光处理使得西葫芦叶片上下表皮细胞密度、细胞直径、气孔密度以及气孔长度均变小,叶片厚度变薄,栅栏组织厚度及叶片厚度均减小,海绵组织也变得更为疏松,栅栏组织/海绵组织的比值减小,细胞间隙变大。     

南宁市大棚早春越夏种植水果黄瓜的小气候评价与调控

对南宁市大棚小气候特征和水果黄瓜生长所需环境条件进行对比分析,结果表明,从水果黄瓜整个生长期来看,棚内光照强度不足,远低于其光饱和点,多云阴雨天气则更差;从播种至开花结果期,棚内平均昼温偏低;结瓜期棚内平均昼温偏高,平均夜温很高,4～9月棚内的平均夜温均在20℃以上,高出其最适夜温上限温度2.7～9.1℃,而且导致昼夜...     

糖能兼用甘蔗新品系宿根季评价

对近年选育的12个参试品系进行了产量、品质及其主要工农艺性状研究,结果表明：FN02-3924、FN02-5707和FN02-20169表现早熟、高产、高糖,且工农艺综合性状优良,推荐进一步试验研究,可望选育成为糖能兼用甘蔗新品种;FN02-6427也具有早熟、高产、高糖和茎粗等优点,但较早开花,有一定的推广价值,宜较早收获。早期锤度研究表明,FN02-3924特早熟高糖,作能源甘蔗可提早2个多月开榨,具有广阔的应用前景。     

Effects of vegetable oil supplementation on feed intake,rumen fermentation,growth performance,and carcass characteristic of growing swamp buffaloes

Fifteen, one year old swamp buffalo males with average liveweight of 200.5 ± 9.5 kg were randomly assigned according to a completely randomized design to receive three dietary treatments of supplemental vegetable oils in concentrate contained 140, 750, and 16 g of crude protein, total digestible nutrient, and ether extract, respectively (T1 = unsupplemented, T2 = supplemental coconut oil and sunflower oil in ratio 50:50 at 6% of concentrate, and T3 = supplemental sunflower oil at 6% of concentrate) during a 5-month feeding trial. Urea-treated rice straw was offered ad libitum and concentrate was supplemented at 150 g/kg BW. The results revealed that supplementation of vegetable oils decreased dry matter intake in sunflower oil supplemented group. Combination of coconut oil and sunflower oil supplementation resulted in similar average daily gain as those found in control and in sunflower oil supplemented groups. Rumen microorganism population, ammonia–nitrogen, blood urea–nitrogen and total volatile fatty acid concentrations were decreased as vegetable oils were supplemented. Oil supplementation slightly reduced growth rate, hot carcass percentage, loin eye area particularly on sunflower oil supplemented group. Based on these findings, vegetable oil resulted in decreased performance of swamp buffaloes although the combination of coconut oil and sunflower oil could reduce negative effect of unsaturated oil supplementation. However, further analyses of conjugated fatty acids (CLA) in meat could offer useful information in determining pronounced effects of vegetable oil supplementation.     

Effect of hot air,UV-C,white light and modified atmosphere treatments on expression of chlorophyll degrading genes in postharvest broccoli (Brassica oleracea L.) florets

Several treatments were applied in order to delay postharvest degreening in broccoli florets and investigate their effects on genes associated with chlorophyll catabolism. Degradation of chlorophylls is the most evident visual manifestation of broccoli postharvest deterioration, occurring rapidly due to the immature stage in which the material is harvested. Treatments such as storage in modified atmosphere, exposure to hot air, UV-C and white lamps were employed in the current work to induce a delay in degreening and chlorophyll degradation. Expression of genes possibly related to chlorophyll catabolism was analyzed in these samples and discussed. Chlorophyllases, the enzymes traditionally believed to remove the phytol side chain from chlorophyll appear to have a gene expression that was not regulated by postharvest treatments. Pheophytinase, a recently discovered new enzyme in this metabolic pathway, correlated chlorophyll loss accurately in heat, UV-C and white-light treatments, but not in modified atmospheres. Results presented in this work indicate that postharvest treatments that delay chlorophyll degradation have a higher effect on the expression of pheophytinase rather than on chlorophyllase genes.     

Factors affecting in vitro adventitious shoot formation on internode explants of Citrus aurantium L. cv. Brazilian

The in vitro formation of newly formed adventitious buds and shoots from internodal branch segments was studied on 12-month-old plants of Citrus aurantium L. cv. Brazilian. The effects of 6-Benzyladenine (BA) and α-Naphthalene acetic acid (NAA) treatments were evaluated on adventitious bud and shoot regeneration. High rates of bud initiation and shoot development were obtained both with BA supplemented medium, in the range from 1 mg L⁻¹ to 3 mg L⁻¹, and with 0.1 mg L⁻¹ NAA supplemented medium. NAA concentrations above 1 mg L⁻¹ significantly reduced bud initiation and shoot elongation. The results obtained using different in vitro culture vessels such as Petri dishes, tubes and glass culture jars were compared. The highest adventitious bud induction was observed in Petri dishes for internodes cultured in 2 mg L⁻¹ BA supplemented medium, with 95% responsive explants forming 9.0 ± 2.4 adventitious buds. The adventitious buds observed in Petri dishes reached a maximum height of 1 mm, with no further development, while some of the adventitious shoots cultured in tubes and glass culture jars grew over 1 cm in height. A shoot regeneration gradient of the internodes collected along the branch axis was noticed, with basal ones exhibiting higher regeneration frequency.     

Defense response of tomato fruit at different maturity stages to salicylic acid and ethephon

In order to elucidate whether fruit maturity stage influence the induced resistance of exogenous elicitors in tomato and the involved mechanisms, we investigated the defense responses of tomato fruits against Botrytis cinerea, ethylene production and internal quality following treatments of fruit with salicylic acid (SA) or ethephon (ET) at mature green (MG) and breaker (BR). SA significantly suppressed decay and disease incidence in tomato fruits at both MG and BR stages, along with higher expression level of PR1 gene after 2 days of treatment. All fruits treated by SA had lower contents of ethylene and lycopene. The ET-treated fruit at both maturity stages showed lower disease incidence and higher level of PR2 and PR3 expression compared with the control fruit. ET treatment significantly enhanced ethylene and lycopene contents, and accelerated fruit ripening. Our results suggest that SA and ET induced disease resistance in fruits by mediating the expression of different pathogenesis-related genes and have different effects on fruit ripening, which in turn influences the disease resistance of tomato fruits.