The Effect of Pretreatment Period and 2,4-D Concentration on Anther Culture of Pepper Hybrid ‘Pak Klong’

Abstract

Double haploid lines are useful in generating material for parental line in hybrid development. This research was to study the effect of pretreatment period and 2,4-D concentration on anther culture of pepper conducted at Chiangrai Highland Agricultural Research and development Center during  2020-2021. Anther culture of F₁ hybrid chili pepper var. ‘Pak Klong’ was performed. Anthers containing microspores at the late uninucleate stage were collected and cultured on C medium supplemented with 0.1 and 0.3 mg/l of 2,4-D and 0.1 mg/l kinetin. The cultured plates were incubated at 35^OC for 4, 6 and 8 days and moved to 25^OC in the dark for 10 days. Then anthers were transferred to R medium containing 0.1 mg/l kinetin under 16 h day length. Forty days after culturing, embryos emerged from anthers which were transferred to the plant growth regulator free R medium. The highest number of embryos developed to plantlets was 5.8 plantlets/100 anthers when cultured on C medium containing 0.1 mg/l 2,4-D plus 0.1 mg/l kinetin in the dark at 35 °C or 6 day. Chloroplast counting could be used to determine the ploidy level. The investigation of whether diploid plants were derived from spontaneous chromosome doubling was done by using a microsatellite marker. The results revealed 18 haploid plants and 22 spontaneous double haploid from 1,270 anthers.