Increasing Maize Pollen Viability with NPK and Boron, and Its Utilization in Hybrid Seed Production

Abstract

Maizeis one of food crops targeted to be self-sufficient in 2014, thus production should be increased to meet the demand. One way of increasing the production is use of hybrid seeds which is not always available for farmers due to low seed production of F1 hybrid. The low production of the F1 hybrid is hindered by the low pollen production, short pollen viability, and unsynchronized flowering of male and female parents. Therefore, increasing pollen viability as well as prolong storability of the pollen using NPK and boron would ensure the availability of pollen for hybrid seed production. The research was conducted in the experimental station of Puspiptek and Seed Technology and Agro-Industrial and Biomedical Development (Laptiab) laboratory, BPPT, Serpong. The research was carried out during April to November 2013, consisted of two experiments to study the effect of NPK and boron on pollen production and viability; and to investigate the effect of temperature and prolonged storage of pollen on maize hybrid seed production. The male parent of hybrid maize Bima 3 (strain M14 ) was used in the first experiment that was arranged in split plot design with three replicates. The main plot was dosage of NPK i.e. 0, 300 and 600 kg ha-1. The sub plot was dosage of boron i.e. 0, 1, 2, 3 kg ha-1. The result showed that NPK increased plant height and number of leaves, shorten the time of emergence of tassel (J50%), increased the number of spike per tassel, spike length and pollen viability. Application of boron increased the number of spike per tassel, lengthened the spike and increased pollen viability. NPK 600 kg ha-1 and boron 3 kg ha-1 increased the number of spike per tassel, spike length, and pollen viability. In the second experiment NPK 600 kg ha-1 and boron 3 kg ha-1 was applied to produce pollen of M14 and then stored and used for hybrid seed production. The female parent of Bima 3 (Nei9008) was used to evaluate if stored pollen was potentially beneficial for hybrid seed production. The experiment was arranged in completely randomized design with two factors and three replicates. The first factor was storage temperature i.e. -20 °C and-40 °C, and the second factor was storage period i.e. 0, 1, 2 and 3 weeks after storage (WAS). The results showed that both the storage temperature -20 °C and -40 °C were able to maintain the pollen viability above 85% for 3 WAS based on I2KI stain. However, the stored pollen was not effective for hybrid seed production due to very low seed set. Seeds obtained from stored pollen had lower germination percentage, vigor index and germinated slower than those obtained from fresh pollen.