Abstract Under laboratory experimental condition female Adzuki bean beetles, Callosobruchus chinensis (L.) are known to evenly distribute their eggs over grains available for egg laying. However, currently there are no data on pattern of egg distribution by Adzuki bean beetle in large quantity of chickpea grain stored for extended period of time. The objective of this study was to determine the number and distribution of eggs among grains of chickpea stored in large quantity for 8 months and subjected to natural infestations. The experiment was conducted under room temperature and relative humidity at Debre Zeit Agricultural Research Center. The chickpea cultivars used were Natoli (desi type, 22 g per 100 seeds with Tuberculated seed coat texture) and Arerti (kabuli type, 26 g per 100 seeds with smooth seed coat texture) and for each cultivar there were 21 replicas of bags (40 cm wide and 70 cm high). From each bag, which contains 10 kg each, 25 chickpea grain samples were randomly selected at monthly intervals and examined for the presence or absence of Adzuki bean beetle eggs. Grains with eggs were categorized into frequency classes (i.e. 0, 1, 2, …, n) based on the number of eggs present on them. The variance to mean ratio was used to decide the type of egg dispersion pattern. In all the sampling dates and on both cultivars, the variance to mean ratios were highly significantly greater than one indicating that egg distribution by female Adzuki bean beetles on grains of chickpea was aggregated type. Moreover, further analysis of data had shown that the egg distribution pattern perfectly fits the negative binomial distribution, which confirms that the pattern of egg distribution on chickpea grains was aggregated/clumped type.

中文翻译：

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小豆甲虫，Callosobruchus chinensis (L.)（鞘翅目：Chysomelidae）在自然侵染下储存的鹰嘴豆中的卵分布模式

摘要 在实验室实验条件下，雌性红豆甲虫 Callosobruchus chinensis (L.) 已知将它们的卵均匀分布在可产卵的谷物上。然而，目前还没有关于红豆甲虫在长期储存的大量鹰嘴豆粒中的卵分布规律的数据。本研究的目的是确定大量储存 8 个月并遭受自然侵扰的鹰嘴豆谷物中鸡蛋的数量和分布。实验在室温和相对湿度下在 Debre Zeit 农业研究中心进行。使用的鹰嘴豆品种是 Natoli（desi 型，每 100 粒种子 22 g，具有结核种皮质地）和 Arerti（kabuli 型，每 100 粒种子 26 g，具有光滑的种皮质地），每个品种有 21 个袋子的复制品（40 厘米宽和 70 厘米高）。从每个袋子（每袋 10 公斤）中，每隔一个月随机抽取 25 个鹰嘴豆粒样品，并检查是否存在红豆甲虫卵。带有鸡蛋的谷物根据其上的鸡蛋数量被分为频率等级（即 0、1、2、...、n）。方差与平均比用于决定鸡蛋分散模式的类型。在所有采样日期和两个品种中，均值比的方差显着大于 1，表明雌性小豆甲虫在鹰嘴豆粒上的卵分布是聚集型的。而且，