Standardization of In Vitro Pollen Germination Medium of Two Economically Important Plants: Brassica juncea (L.) Czern. and Lens esculenta M.

Abstract

Pollen fertility and viability are essential for fruit and seed set in angiosperms, as well as for the successful development of hybrid plants and storage of germplasms. Our study focused on identifying the optimal culture medium for in vitro pollen grain germination and growth of pollen tube for two commercially important crops Brassica juncea and Lens esculenta. Percentage pollen fertility was analyzed using 1% acetocarmine solution. After ten days, pollen fertility decreased from 100% to 75.14±2.69 % and 72.31±2.52% for B. juncea and L. esculenta, respectively. SGM for pollen germination and tube growth in B. juncea contain boric acid (300 mg/L), calcium nitrate (400 mg/L), magnesium sulphate (300 mg/L), potassium nitrate (400 mg/L) along with 15% sucrose. Addition of 15% PEG in SGM gave the highest value for the percentage of pollen germination (52.90±0.72%) and resulted in the maximum length of pollen tube (45.2±4.93μm). SGM for L. esculenta composed of boric acid (200 mg/L), calcium nitrate (400 mg/L), magnesium sulphate (300 mg/L) and potassium nitrate (200 mg/L) supplemented with 15% sucrose. Among the polyamines, 10-4 M spermine gave the best results for the percentage of pollen germination (42.22±1.36%), while 10-3 M spermine showed highest pollen tube growth (80.92±16.57μm). This study will help to establish protocols for in vitro pollen germination and tube growth of several species of plants closely related to Brassica sp. and Lens sp.