PRESERVATION OF GERMPLASM
Most of the seeds lose viability quickly. Consequently germplasm collection have to be grown every few years. The difficulties generally experienced are:
अधिकांश बीज जल्दी व्यवहार्यता खो देते हैं। नतीजतन जर्मप्लाज्म संग्रह को हर कुछ वर्षों में उगाया जाना है। आम तौर पर अनुभव की जाने वाली कठिनाइयाँ इस प्रकार हैं:
- Growing, harvesting and storing large collections is a costly affair requiring much time, labour land money.
- There is also risk of errors is labelling.
- The genotypic constitution of entries may also change, particularly when the y are grown in environments considerably different from that to which they are adapted. This is particularly true in cross-pollinated species and for local varieties of the self-pollinated species.
The difficulties may be considerably reduced by cold storage of seeds. Seeds of most of the plant species can be stored for 10 years or more at low temperature and low humidity. Thus the entries can be grown every 10 years instead of every year. NBPGR has developed cold storage facilities for germplasm maintenance and this is known as National Germplasm Repository.
It is defined as an area of diversity protected from human interference. A gene sanctuary conserves the germplasm insitu, within the environment where it naturally grows. This not only conserves the germplasm with very expensive, but also permits evolution to proceed on its natural course.
इसे मानव हस्तक्षेप से संरक्षित विविधता के क्षेत्र के रूप में परिभाषित किया गया है। एक जीन अभयारण्य जर्मप्लाज्म इंसेटु का संरक्षण करता है, जहां यह स्वाभाविक रूप से बढ़ता है। यह न केवल बहुत महंगी के साथ जर्मप्लाज्म का संरक्षण करता है , बल्कि इसके प्राकृतिक पाठ्यक्रम पर आगे बढ़ने के लिए विकास को भी अनुमति देता है।
This allows the appearance of new gene combinations and new alleles not present in the pre existing population. NBPGR has established gene sanctuaries in Meghalaya for citrus and in the North Eastern region for Musa, Citrus, Oryza, Saccharum and Mangifera.
are trips for the purpose of collection of various forms of crop plants and their related species. Exploration generally cover those areas that are likely to show the greatest diversity of forms.
The centres of origin are such areas and are often visited by various exploration teams. In addition to wild flowers, lend and open pollinated varieties are also collected. Exploration is the primary source of all the germplasm maintained in germplasm collections.