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Mohamed Mahmoud Sidina Mohammed El Hansali Nadia Wahid Aziz Ouatmane Abdelali Boulli Abdelmajid Haddioui 《Scientia Horticulturae》2009,123(1):110-116
The carob tree (Ceratonia siliqua L.) is an important economic resource for Morocco's rural populations. This species is used in reforestation actions and its cultivation in modern orchards is being undertaken to valorize marginal lands and substitute for drought sensitive species. However, little data is available on its intra-specific variability and its adaptability. Morphological characters of pods and seeds from 13 ecoregions of private-domesticated carob were used to assess phenotypic variation of this species. These stands extend from south-west to north-east and cover a wide range of Morocco's ecoregions. Pods length, width, thickness, seeds number, pulp weight, seeds yield and seeds length, width, thickness and weight were measured for 390 trees (30 trees per ecoregion). Statistically significant differences were found between ecoregions for all characters which were examined, what indicates a high phenotypic diversity. Principal component analysis (PCA) and hierarchical cluster of all ecoregions lead to identify two major and opposite groups (the northern ecoregions; and the central and south-western ecoregions). Ecoregions of the north of Morocco exhibited the largest and the thickest pods with the highest pulp weight while other ecoregions have relatively short pods but largest proportion of seed yield. Similarly, the northern ecoregions are characterized by the heaviest seeds. A correlation matrix between morphological characters, geographic parameters and precipitation exhibits a positive and a negative correlation of pods thickness and pulp weight with the latitude and the altitude, respectively. Seed yield and weight are negatively and positively correlated to pod width, pod thickness and pulp weight, respectively. In addition, seed weight is positively correlated with the latitude. The geographic pattern of the carob tree and its variability are discussed in this paper. 相似文献
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Kouakou Laurent Kouakou Irié Arsène Zoro Bi Yao Georges Abessika Tanoh Hilaire Kouakou Jean-Pierre Baudoin 《Scientia Horticulturae》2009
To develop efficient seedling production methods for Laccosperma secundiflorum and Eremospatha macrocarpa, a study was conducted to examine regeneration using offsets combined with several physical and chemical treatments of seeds. Offsets categorized into small, medium and large diameters, were planted in three conditions: shaded and open nursery, and greenhouse. We tested sucker from E. macrocarpa, and sucker and rhizome from L. secundiflorum. For both species, high viability percentage (ranging from 55% to 100%) were observed for small and medium suckers planted in shaded nursery and greenhouse, against less than 49% for sucker planted in open nursery. The mean seedling emergence times were estimated to 84, 77 and 75 days after planting (DAP) for small, medium and large sucker of L. secundiflorum, respectively under open nursery condition, and 76, 75, 95 DAP for small, medium and large suckers of the same species, respectively in shaded condition. Greenhouse has a significant positive effect on E. macrocarpa seedlings emergence time. For this species, the mean seedling emergence times were estimated to 43 DAP for small sucker and 76, 93 DAP for medium and large suckers. No seedling was obtained from rhizome planted in all the growing conditions tested. Concerning seed dormancy breaking, germination percentages and rates were determined for 13 treatments. The best treatments were pre-soaking unscarified seeds for 4 days in 1.01 g l−1 and 0.10 g l−1 KNO3, with 79% and 68% of germination, respectively and in 3.46 × 10−3 g l−1 GA3 for 68% of germination. These methods are suggested to improve germination of L. secundiflorum seeds. Successful and recommended methods for E. macrocarpa are pre-soaking scarified seeds in 3.46 × 10−3 g l−1 and 3.46 × 10−4 g l−1 GA3, 96% and 94% of germination, respectively. Dormancy, probably a combination of mechanical and chemical dormancy, is present in the two species. 相似文献
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The effects of three set-sizes (12.5, 17.5 and 22.5 mm in diameter) and seven storage temperatures (0, 5, 10, 15, 20, 25 and 30 °C) on bolting, bulbing and seed yield in two onion (Allium cepa L.) cultivars ‘Hygro’ and ‘Delta’ were investigated. The incidence of bolting increased linearly with set-size and curvi-linearly with decreasing storage temperature. Time to inflorescence emergence and floret opening showed a curvi-linear response to storage temperature with the earliest inflorescence emergence and floret opening occurring at 5 °C and the latest at 30 °C for ‘Hygro’ and at 25 °C for ‘Delta’. Seed yield per umbel also showed a curvi-linear response to storage temperature with the lowest seed yield occurring at 30 °C for ‘Hygro’ and at 25 °C for ‘Delta’ and the highest seed yield at 5 °C. For a seed crop, storage of large sets (22.5 mm) of these cultivars at 5 °C for 120 days appeared to be optimum with 5–12% higher seed yield per umbel than that of 90 days storage. Bulb yield showed a curvi-linear response to storage temperature with the highest bulb yield occurring at 25 °C and the lowest at 5 °C. 相似文献
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苜蓿花期调控与传粉效率的研究 总被引:1,自引:0,他引:1
针对苜蓿花期与昆虫活动不遇的问题,通过刈割进行花期调控,以提高初花期及盛花初期的传粉效率,并探讨对种子产量及构成因素的影响.结果显示:刈割后苜蓿的花期明显推迟,传粉效率显著提高,其中访花频次由原来的23次/10m2·d提高到刈割后的180次/10m2·d;在初花期及盛花初期标记的花序结荚率及荚内种子粒数分别由对照的(17.12±2.83)%和(3.94±0.31)粒提高到刈割后的(84.1±1.21)%和(5.31±0.22)粒;整个花期的平均结荚率/花序由刈割前的43.77%增加到刈割后的59.43%;刈割后的苜蓿种子产量与各构成因素的相关性依次为:花序数/枝>荚果数/枝>荚内种子粒数>结荚率/花序>分枝数>单花数/花序.对种子产量与构成因素进行多元回归分析,单枝条产量(Y)与花序数/枝(X1)、结荚率/花序(X2)具有真实回归关系Y=-1.735+0.034 X1+0.036 X2(R=0.788).在该地区确定适宜的刈割时间可明显推迟花期,提高种子产量.合理的刈割时间是在花期得到推迟的情况下,使生育期尽可能长. 相似文献
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强酸性电解水浸种对黄瓜种子发芽与幼苗生长影响的研究 总被引:1,自引:1,他引:1
研究了不同浓度(有效氯浓度)强酸性电解水浸种对黄瓜种子发芽与幼苗生长的影响, 结果表明:低、中浓度电解水对黄瓜种子发芽率没有影响,高浓度电解水会抑制种子发芽;适宜浓度电解水浸种可提高种子胚芽生长速率,促进黄瓜幼苗生长与干物质积累,提高黄瓜幼苗素质,而高浓度电解水则产生抑制作用;黄瓜浸种适宜的电解水指标为:pH 2.35左右、ORP 1135mV左右、有效氯浓度 30 mg·L-1左右。 相似文献
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介绍大连地区2种主要外来入侵杂草发生情况、植物学特征及防治措施,为林业安全生产提供基础性参考意见。 相似文献