A Field Study on Foraging Speed of Apis mellifera and Apis florea on Nine Cultivars of Brassica
Braj Kishor Prasad Singh *
University Department of Zoology, Babasaheb Bhimrao Ambedkar Bihar University, Muzaffarpur-842001, Bihar, India.
Prabal Chatterjee
Ramdayalu Singh College, Babasaheb Bhimrao Ambedkar Bihar University, Muzaffarpur-842001, Bihar, India.
*Author to whom correspondence should be addressed.
Abstract
Honey bees are important pollinators of Brassica crops, and their foraging behaviour can vary among bee species and crop cultivars. However, comparative field information on the time spent per flower by Apis mellifera and Apis florea across different Brassica cultivars under local field conditions remains limited. Understanding such variation is important for characterising bee–cultivar interactions associated with pollination. The study addresses an important aspect of pollination ecology by comparing the foraging speed of Apis mellifera and Apis florea on nine cultivars of Brassica. The crops were grown in 2 m x 4 m agricultural field plots following locally recommended agronomic practices at Mushari Block, Muzaffarpur district, Bihar, India. Fieldwork was conducted over two consecutive rabi seasons, 2022-2023 and 2023-2024, and the data were analysed using a factorial randomised block design with three replications at the University Department of Zoology, B. R. A. Bihar University, Muzaffarpur. The crops were sown on 1 November in each experimental year, and data were collected from 21 December to 18 January at weekly intervals using a chronometer (stopwatch) with an accuracy of 0.01 second. The treatments were compared at the 5% level of significance. The observations suggested that, within the three crop groups, both A. mellifera and A. florea spent the maximum time on cv. Varuna of Brassica juncea var. Raya, cv. Panchali of Brassica campestris var. Toria, and cv. Jhumka of Brassica campestris var. Sarson, whereas the corresponding minimum times were recorded on cv. Pusabold of B. juncea var. Raya, cv. T-9 of B. campestris var. Toria, and cv. Rajendra Sarson-1 of B. campestris var. Sarson. The study provides valuable insights essential for enhancing agricultural productivity and crop pollination. Field observations over two consecutive years provide important information on cultivar attractiveness.
Keywords: Apis mellifera, Apis florea, Brassica juncea, Brassica campestris, foraging speed