Udhayam

A single plant selection belonging to Pisang Awak (ABB) subgroup. The average bunch weight is 37 kgs and has a potential to yield upto 45 kgs under good manangement practices. It gives 40 per cent higher yield than local Karpuravalli. Crop duration is 14 - 15 months and yield remains stable even in ratoons. Exhibits field tolerance to Sigatoka leaf spot and nematodes. The cylindrical bunch and well spaced hands makes it suitable for long distance transportation and less prone to fruit damage during transit. It has high sugar content with 31oB with harmonious blend of acidity and sweetness and hence suitable for making banana fig and juice.

Conservation

NRCB, Trichy designated as one of the National Active Germplasm Sites (NAGS) and has the responsibility of conserving Musa diversity. Ex situ conservation is being done in field with in vitro, seed and DNA banks.

• Field genebank at NRCB, Trichy is one of the Asia’s largest genebanks with 340 indigenous accessions and true representation of the Musa diversity of the Indian subcontinent. The germplasm has an addition 70 exotic accessions.
• The concept of DNA as a gene bank resource has emerged in genomic information. Therefore, DNA has been isolated from all the germplasm accessions and a DNA bank has been established with 310 indigenous and 30 exotic accessions at NRCB, Trichy. Seed bank has also been established and it possesses both the seeds of wild varieties and hybrids produced through conventional breeding. This could also be used as a DNA source as novel and validated protocol has been made available for the isolation of seed DNA.

• An in vitro gene bank facility has been created at NRCB, Trichy with 200 germplasm accessions for short term conservation.

Mass multiplication technologies

• Tissue culture protocols have been standardized for Indian fragrant landraces viz., Manoranjitham (AAA), Hill banana (AAB), Ladan (AAB) and Udhayam (ABB). The landraces have been reintroduced into their natural habitats. More than 3000 nos. of planting material of NRCB released variety, Udhayam has been supplied to the interested growers.
• ECS as a source for mass multiplication has been evaluated for cvs. Nendran, Rasthali, Grand Naine, Robusta and Ney Poovan. ECS derived plantlets of Rasthali and Nendran have also been evaluated for genetic fidelity under field conditions and their performance was found to be on par with sucker derived and tissue culture plants. This could also serve as the basic in vitro system for genetic transformation and induced mutagenesis.
• DNA fingerprinting has been developed for the NRCB released variety Udhayam using SSR markers and the primer pairs namely AGMI 35/36, 67/68, Mb SSR 1-100 and Mb SSR 1-149 produced alleles of sizes 111bp, 145bp, 271bp and 281bp respectively and those were specific for Udhayam.
• Protocol has been standardized for genetic fidelity testing using ISSR markers and services are being provided to various tissue culture companies as per the DBT-ATL norms for the production of disease free, quality planting material.
• Macropropagation - a simple, viable and farmer friendly technology has been developed as a suitable alternative for tissue culture multiplication and the technology has been well demonstrated in commercial varieties of banana.
• A protocol consisting of growth regulator combination, optimum maturity stage at which embryos to be rescued and cultured in vitro have been standardized. This has paved way for the easy regeneration of wild varieties and hybrid progenies.
• Suppressive Subtractive Hybridization has been performed with contrasting parents for Sigatoka and nematode resistance and 3670 differentially expressed transcripts have been captured.
• 805 ESTs have been deposited at NCBI-GenBank in the category of Metallothioneins, Catalase, Rubisco Activase, Hypothetical proteins, patents predicted proteins, Cystine protease, Ubiquitin conjugating enzyme, ATP synthase, Retrotransposans, Plastocyanins, Cytochrome oxidases, hypothetical mRNA and new types of ESTs which do not show similarity with any of the GenBank data.
• Screening of banana germplasm for nutritional diversity, identified varieties rich in micronutrients and carotenoids.

Genetic resource management

ICAR - National Research Centre for Banana, Trichy serves as the national repository for banana and plantains, involved in collection of banana germplasm from India and abroad. Systematic characterization has led to the establishment of a core collection with 310 accessions representing entire banana diversity. The centre has identified six new species and landraces. The entire germplasm is conserved in field gene banks which is one of the Asia’s largest gene banks. Some of the delicate accessions are conserved in the Satellite field gene Bank maintained at Agali, Kerala of ICAR-Sugarcane Breeding Institute. NRC for Banana also maintains DNA bank and cell lines bank while the in-vitro and cryo gene banks are being maintained in collaboration with ICAR-NBPGR, New Delhi.

Varieties

With concerted efforts, the centre has released three high yielding varieties namely Udhayam, Saba and Bangrier which are known for leaf spot resistance, tolerance to drought and salt stress and short duration respectively. In addition, three more varieties are in the pipeline for release. The varieties are Namwa Khom, an extremely dwarf variety which does not require propping suitably fit for cyclone prone coastal area; Popoulou, which is rich in carotenoids and suitable for preparing value added products and a Manoranjitham selection with high yield and a fragrant variant.

Hybrid bananas and mutants

With the help of embryo rescue technology and embryo culture protocol, we have enhanced the hybrid seed regeneration. Out of 1000’s of hybrid seeds obtained, two Nendran based hybrids with higher yield, high PVA content (23%) and tolerance to Fusarium wilt race-1 and two Saba based hybrids with higher yield, mealy cooking texture and drought tolerance are in advance field trials. Two Rasthali mutants and one Cavendish mutant resistant to fusarium wilt race 1 were identified through field screening in sick plots which are going to be screened for TR-4 in endemic areas.

Technologies for planting material

Low cost, farmer friendly macropropagation method (Kela Vruddhi), for mass multiplication of elite clones has been developed. Variety centric and low cost TC protocols were developed.The centre has established ECS for major commercial varieties and an Bioreactor to multiply the ECS is being tested for its commercial feasibility. With international collaboration, the Centre has developed biofortified bananas enriched with vitamin A, iron and also virus resistant transgenic lines which are under confined field trials.

ICAR-NRCB has developed MusatransSSR and Musa Transcriptome databases with wider applications for the scientific community. DUS guidelines have been developed and notified in the gazette.