Skill India

Identification and brief description of propagation technologies in fruit crops

defination sexual reproduction refers to the multiplication of plants by seeds.

seeds are found after successful pollination and fertilization by the union of male and female gametes.

seed propagation depends upon the following conditions

using seed of proper genetic characteristics to produce the cultivar or species of provenance desired this can be accomplished by obtaining seed from a reliable source or dealer.

using good quality seed which germinate rapidly and vigorously to with stand possible adverse environmental conditions in the seed bed and provide a high percentage of usable seedling

manipulating the seed dormancy by apply pre germination treatment lr proper timing of planting

providing proper environmentvfor seed germination i.e. supplying sufficient water proper temperature adequate oxygen and either light or darkness to the seed and resulting seedling until they are well established

advantage sexual method of propagation has several advantages propagation by seed is simple and easy seed propagation is only mean of diversity particularly in the selection of chance seedling tolerance to adverse soil seedling plants are long lived productive and have greater tolerance to adverse soil and climatic conditions and disease seed propagation makes feasible to propogate plants like papata and coconut in which asexual propagation is not common hybrid can only by developed by sexual means

sexual propagation offers opportunities of polyembroyonyvand apomix is which produces true to type plants. seed is the source for production of rootstock for asexual propagation seeds if stored properly can be kept for longer duration period for future use.

disadvantage sexual method of propagation has some disadvantage seedling plants are not true to type the mother plants due to heterozygous nature of fruit plants. seedling plants have long juvenile phase 6 to 10 years and hence flowering and fruiting commences very late sexually raised plants are generally tall and spreading type and thus are cumbersome for carrying out various management practices like pruning spraying harvesting etc.

seeds of many fruits crops are to be sown immediately after extraction from the fruit as they loose their viability very soon e.g. cashew nut jamun jackfruit citrus mango and papaya.the beneficial influence of rootstock on scion variety cannot be exploited in sexual propagation seedling plants usually produce fruit of inferior quality.

seed dormancy the inability of seed to germinate if favourable conditions are provided is known as seed dormancy

methodsvof breaking seed dormancy

to know about technique for breaking different types of dormancy several methods are used for breaking seed dormancy of horticultural crops these are briefly described here under

1. softening seed coat qnd other seed covering this helps in better absorption of water and gases which ultimately leads to better germination of the seed this can be achieved and scarification scarification scarification is the process of breaking scratching mechanically altering or softening the seed covering to make it permeable to water and gases three types commonly used as scarification treatments mechanical chemical and hot water treatment mechanical scarification it is simple and effective if suitable equipment is available chipping hard seed coat by rubbing with sand paper cutting with a file or cracking with a hammer are simple methods useful for small amount of relatively large seed
2. for large scale mechanical scarifiers are used seeds can be tumbled in drums lined with sand paper or in concrete mixers containing coarse sand lr gravel the sand gravel should be of a different size than the seed to facilitate subsequent separation scarification should not proceed to the point at which the seeds are injured and inner parts of seeds are exposed.
3. acid scarification dry seeds are placed in container and covered with concentrated sulphuric acid or HCL in the ratio of one part of seed to two parts of acids the amount of seed treated at any time should be restricted to not more than 10 kg to avoid uncontrollable heating. the container should be of glass earthenwarebor wood non metal or plastic the mixture should be stirred continuosly at intervals during the treatment to produce uniform results.
4. the time may vary from 10 minutes to 6 hours depending upon the species with thick coated seeds that require long periods the process of scarification may be judged by drawing out sample at intervals and checking the thickness of the seed coat when it becomes paler thin the treatment should be terminated immediately.