Site and fruit maturity influence on the quality of European plum in organic production

Information available on the role of site and fruit maturity in the quality of European plums in organic production has not been studied to date. European plum cv. ‘Green Gage’ grown in organic production was harvested in order to study the effect of site and fruit maturity on fruit quality. At harvest, significant differences were found in fruit weight, colour, firmness and TSS between harvest dates, whereas significant differences were found in fruit weight, colour, firmness and fruit Ca content between sites. Differences remained during storage. Fruit weight loss during storage was affected by site. Fruit with high Ca content showed higher firmness both at harvest and during storage. Harvest moment should not be chosen according to date, since differences between sites at the same date have been found. Firmness and colour parameters a* and h° would be useful to distinguish maturity at harvest between different sites and harvest dates. Linear regression between h° and firmness at harvest would allow the use of the h° colour parameter as a non-destructive measurement to distinguish maturity. Organic orchards should keep a minimum level of Ca in order to assure a slower fruit softening during storage.     

适合不同产量的环境下油菜高收获指数的产量构成因素分析

收获指数偏低是制约油菜籽粒产量和产油量进一步提高的瓶颈。为解析适合不同产量的环境下油菜高收获指数的构成因素及形成机制,本研究选择在高产环境下的云南临沧和一般产量的长江流域上游主产区重庆北碚均能正常生长和成熟的321份甘蓝型油菜品种(系)为材料,分析其产量相关性状的变异以及两地间的差异,利用相关分析和通径分析研究籽粒产量收获指数(YHI)、产油量收获指数分别与17个产量组成性状的关系。结果表明,云南高产环境下,油菜高产的主要原因是光照充足、昼夜温差大,导致生物产量高、角果多、每角粒数多,特别是二次分枝角果对产量贡献较大。主序和一、二次分枝的角果数与产量收获指数在重庆均呈显著正相关,而云南环境下主序角果数与产量收获指数呈显著负相关。主序和一、二次分枝的每角粒数均以云南环境下极显著高于重庆环境下,且在两种环境下,主序和一次分枝每角粒数都与产量收获指数和产油量收获指数呈显著正相关,表明每角粒数需要充足的光合产物积累及高效的籽粒填充效率来保证。主序、一次和二次分枝千粒重云南均低于重庆,表明寡日照区域的油菜会减少籽粒数,以保证部分种子的干物质填充。云南环境下,各部位千粒重与产量收获指数和产油量收获指数均呈显著正相关,而重庆环境下的相关性不明显,说明在光照充足条件下,光合产物转运能力是导致千粒重差异的主要原因。综合分析表明,在光照充足的环境下,主序角果数和单株经济产量是提高YHI的关键;而寡日照环境下YHI构成复杂,必须将主序和一次分枝的产量组分有机结合,且严格控制生物产量才能实现YHI的提高。     

Physicochemical analysis of mountain bananas from the French West Indies

The physicochemical characteristics of bananas grown at two different altitudes (L: 50 m and H: 300 m) in Martinique, French West Indies (FWI) were compared at four harvest stages with the aim of potentially promoting mountain bananas – which differ from current standard bananas – or export to the European market. At an equivalent harvest stage, highland (H) bananas were significantly thicker in diameter (grade), denser and firmer than lowland (L) bananas. After ripening, H bananas were significantly firmer and their peel was harder as compared to L bananas. Their dry matter and dry soluble extract contents and citrate concentrations were significantly higher than noted in L bananas. P contents were significantly higher in L bananas whereas Zn contents were higher in H bananas. A principle component analysis differentiated H and L bananas on the basis of their physicochemical characteristics. It was found that the “altitude” factor had a more marked effect than the “harvest stage” factor on the physicochemical characteristics of ripe fruit.     

直干桉引种及培育技术研究

借用凉山州西昌市、会理县引种直干桉栽培经营期间固定观测和临时调查数据,采用定量与定性相结合的方法,对四川直干桉适生区立地因子、关键造林技术和各类成熟龄进行了探讨,提出了直干桉适宜发展范围和最佳收获期,为直干按原料林基地的集约经营提供参考。     

亏缺灌溉下小麦水分利用效率与光合产物积累运转的相关研究

在大田栽培条件下,以小麦旱地品种晋麦47和西峰20、水旱兼用型品种石家庄8号和水地品种4185为材料,分别进行0水（T0）、一水（T1）和二水灌溉（T2）处理（每次灌水量60 mm）,研究了光合速率、叶面积指数、干物质积累与分配、根系分布、耗水量、产量因子与水分利用效率（WUE）的关系。结果表明,在拔节前不灌溉,拔节到开花期亏缺灌溉,促进干物质积累和深根发育。随着灌溉水的增加,耗水量显著增加,产量和WUE与耗水量呈二次曲线关系。T0处理显著减少了干物质积累和成穗数,产量、经济系数（HI）和WUE最低。T1和T2产量的提高主要是增加了穗数和穗粒数。灌浆期水分亏缺降低了光合速率（P_n）和气孔导度（G_s）,加速了功能叶片的衰老,但诱导了花前储存碳库的再转运,显著提高了HI和产量。因此,在拔节和开花期亏缺灌溉促进根系生长,提高了土壤水分的利用效率。而产量和产量WUE的提高主要是由于增加了灌浆期叶片的P_n和光合功能持续期,促进花前储存碳库的再转运,显著提高了HI。     

多功能植物辣木栽培技术研究初报

在云南省西双版纳州景洪市,通过2003—2006年对辣木栽培技术进行系统研究,经大量试验或实践,提出了一套完整的辣木栽培技术措施,包括种苗繁殖方法、植地的土壤条件、植穴规格、种植密度、施肥、修剪、主要病虫害及其防治、采收、除草、间作等栽培技术措施     

刈割到青贮填装前乳酸菌的动态变化

为调查收割至青贮装填前乳酸菌的动态变化,本研究以甜玉米(Zea mays L.)和热研四号(Pennisetum purpureum×P.americanum‘Reyan No.4’)王草为材料,检测从刈割、切短、放置8h和放置24h四个阶段乳酸菌的动态变化。研究结果表明:从未切短(4.25lg cfu·g~(-1) FM)到切短(5.69lg cfu·g~(-1) FM)阶段乳酸菌的数量显著增加(P0.05),主要是乳酸乳球菌(Lactococcus lactic)、柠檬明串珠菌(Leuconostoc citreum)和融合魏斯氏菌(Weissella confuse)。随着放置时间的延长,乳酸菌种类变化随植物品种而异,甜玉米切短后发现柠檬明串珠菌,放置24h后发现假肠膜明串珠菌(Leuconostoc pseudomesenteroides),而热研四号王草切短后菌株短乳杆菌(Lactobacillus brevis)消失。     

甘草栽培技术

甘草是多年生草本植物,耐干旱贫瘠,适应性强,是防沙治沙的优良先锋草种,本文通过介绍甘草的栽培技术,达到改善生态环境,调整林业产业结构的目的。     

披尔兹番荔枝引种研究

对引进良种披尔兹番荔枝与本地栽培品种普通番荔枝的生长结果特性、果实经济性状、适应性和抗逆性等进行比较研究,结果表明,披尔兹番荔枝每年1-2月落叶,3月下旬开始抽梢,4月上旬现蕾,在枝梢生长季节内可多次开花。通过夏季修剪,披尔兹番荔枝的主产期可以从秋季调节到冬季。苗木栽植第2年开始开花结果,5年生平均产量15246kg／hm2。披尔兹番荔枝果实品质好,单果重269g,可溶性固形物达25.3％,可食率达81％,总糖含量21.9％,酸含量0.3％,Vc 42.4mg／100g。冬季挂果期抗寒力较强。     

我国玉米收获机械发展现状及展望

介绍了玉米收获机械的发展过程,阐述了我国玉米收获机械的种类及特点,分析了当前玉米收获机械发展中存在的主要问题,同时提出了为提高玉米收获机械化水平所采取的主要措施。