Project Record

Objectives:

Identification of genetic diversity, selection and development of propagation systems of Jackfruit and Pummelo.

Background:

Jackfruit, pummelo and mandarin are high quality priority species for natural and landless farmers, an there is a potential for increasing productivity of quality produce through selection, evaluation, propagation and ultimately breeding. Mandarin is particularly important for mid hill areas in Nepal. The lack of improved planting materials and access to information by farmers is a major constraint to improvemtn. Standardisation of rootstocks using both vigorous and dwarfing rootstocks can pave the way for better production of mandarin in the mid hill situation in Nepal. Targetted research activities will enable the distribution of good quality planting materials to poor farmers.

Intended Outputs:

Collection of jackfruit and pummelo established.
Catalogues of germplasm.
Varieties selected for propagation, sale and distribution by farmers.
Propagation systems which work.
Staff trained.
Technology dissemination
Technically trained staff of national research institutes.
Technology for target institutions, such as IPGRI, NARS, CIFOR in the region for their use.

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Progress and Impact:

A total of 70 jackfruit and pummelo accessions from five different agro-ecological zones were collected and established at the Horticulture Research Centre, Joydebpur.

Germplasm catalogues of pummelo and jackfruit were produced.

Germplasm of jackfruit and pummelo was evaluated through farmers' participatory surveys and laboratory analysis. A wide variation of morphological characters of tree, fruit, leaves, and seed was identified, in both jackfruit and pummelo, from farmers' information and laboratory analysis. On the basis of farmers' choice, six and ten superior tree types of pummelo and jackfruit respectively were selected for propagation and distribution to farmers . The factors controlled by environmental influences were also considered for selection.

Vegetative propagation:
Pummelo: Cuttings, air-layering, and six grafting methods were used to identify the most suitable growth regulators, time, and methods for vegetative propagation. It was observed that cuttings taken in the month of June without any treatment of growth regulator, and grown in soil/sand mixtures, produced a higher number of roots, and no significant differences were observed when treated with growth regulators. However, higher success was noted when cuttings were taken in the month of April, for establishment in the nursery. Air-layering with commercial coir dust and cocopit mixture media gave high success in July. It was found that branches of less than 20 year old trees exposed to sunlight, gave higher success in air-layering in the mid-hill and Terai areas. Shoot-tip, cleft, veneer, saddle, and whip and tongue grafting methods with scion from 10 year old trees on two rootstocks (rough lemon and trifoliate orange) were tried. 80-90% success was recorded with all grafting methods, but scion and both rootstocks were found to be compatible when veneer and cleft methods were used.

Jackfruit: Budding, air-layering and four grafting methods (veneer, cleft, splice and epicotyl) were tried, to identify the best suitable growth regulators, time, and methods. Budding was not found to be suitable, but 80% air-layers were established when taken in November and treated with 2000ppm of IBA. Evaluation of grafts obtained from different months, and using different methods, were carried out, and the highest growth was achieved when the veneer method was used in April, on 3 months' old rootstock.

In vitro propagation:
Pummelo: Explants cultured on a medium containing 0.4 mg/lit BAP produced the highest number of shoots (4-6) after 40 days. Since there was no elongation of shoots, the explants were transferred to the media containing 2mg/lit GA3 plus 0.4mg/lit BA. 3-8 additional shoots per explant were produced in every 3 week period.

For root initiation, half strength MS media supplemented with 0.25mg/l and 0.5mg/lit NAA was found to be most suitable.

The regenerating plantlets were hardened initially at a room temperature of 25-30C for three months, before establishing them in the greenhouses.

Jackfruit: A comparative study shows that BAP with concentration of 2mg/l in the media provide good shoot proliferation. However, TDZ with concentration of 0.50mg/l generates more shoots than any other cytokinins used for shoot proliferation.

For root initiation, half-strength MS media supplemented with 2mg/l IBA was found to be suitable.

Plant establishment: The regenerating plantlets were hardened iniitially at a room temperature of 25-30C for two months, until new leaves were seen. These plantlets were transferred to the greenhouse for establishment. The success for establishment of plantlets in the greenhouse was about 88%.

Two scientists, from Bangladesh and Nepal, were trained in the use of techniques, and how to analyse data statistically.

An annotated bibliography has been published on both species. Catalogues for species have also been published.

Project Conclusions:

The project has successfully identified quality trees of jackruit and pummelo for clonal propagation. Both vegetative and in vitro propagation methods have been developed, both for propagation, and to distribute quality planting materials to farmers. This would improve nutrition, and raise income in Bangladesh and Nepal, and the propagation methods could also enhance the production of planting materials in other UTFANET member countries. The knowledge gained from the project has been disseminated, and the project met generic goals.

Paper File Reference:

NRC 9597 832/531/001a