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Objectives of Plant Breeding

Major Objectives of Plant Breeding Program Plant breeding is an important branch of agricultural science. Its main purpose is to develop new and improved crop varieties. These improved varieties give better yield, better quality, and better resistance against diseases and harmful environmental conditions. A plant breeding program is planned according to the needs of farmers, consumers, industries, and climate. The major objectives of plant breeding are explained below in simple paragraph form. 1. Higher Yield The first and most important objective of plant breeding is to increase crop yield. Food demand is increasing due to rapid population growth, so breeders try to develop varieties that produce more grains, fruits, seeds, or biomass per unit area. High-yielding varieties help farmers earn more profit and improve food security. This is why yield improvement is considered the central objective of every breeding program. 2. Improved Quality Another major objective is to improve t...

Isolating mechanisms" available in nature.

Discuss the different “isolating mechanisms" available in nature. The development of differentiation in sympatric populations which are  those inhabit the geographical area, will not interbreed even when kept  together. Such a situation results due to varied factors which are collectively  caused isolating mechanisms. Isolating Mechanisms :  The isolating mechanisms may be purely spatial  or may involve specific mechanisms covering reproductive isolation, which  will operate in sympatric population. Setbbins in his recent book, Processes  of Organic Evolution, classified reproductive isolation mechanisms into two  types: (a) Prezygotic mechanisms :   These prevent contact between species at  the time of active reproductive period or else the fertilization is checked even  if pollination may be effectively brought about. These may be:  (1) Spatial or  ecological isolation,  (2) Seasonal or temporal isolation,  (3)...

MCQ BIOLOGY (SOLVED) FOR NEET & JEE -15 JANUARY 2021

  1. Lyon's hypothesis ­L¡e¢Vl p­‰ pÇf¢LÑa ? (a) h¡lh¢Xl pwMÉ¡                                      (b) ­S­e¢VL LjfÉ¡¢V¢h¢m¢V            (c) ­S­e¢VL CeLjfÉ¡¢V¢h¢m¢V                       (d) ­p­¸VÊ¡¢ju¡­ll AhÙÛ¡e   2. HLSe Ù»£­m¡­Ll ¢nöl klinefelter ­l¡N q­u­Rz ¢nö¢Vl ­c­q h¡lh¢Xl pwMÉ¡ La ? (a) 1      (b) 2      (c) 3      (d) HL¢VJ eu   3. Hexaploid   Nj qm - (a) Triticum turgidum   (b) Triticum aestivum   (c) Triticum monococcum        (d) Triticum durum 4. pÉ¡m¡Ci¡l£ NË¢¿Û­a Ah¢ÙÛa puff h¡ h¡m¢hu¡e£ hmu ­L¡e L¡­kÑl p­‰ pÇf¢L...