Plant breeding has been used for thousands of years, and began with the domestication of wild plants into uniform and predictable agricultural cultigens. High-yielding varieties have been particularly important in agriculture. Selective plant breeding is also used in research to produce transgenic animals that breed "true" (i. e.
, are homozygous) for artificially inserted or deleted genes. Over time, selective breeding modifies teosinte's few fruitcases into modern tomato's rows of exposed kernels. In any given reason, reporting tomato could be lost to 10-15%.There was a bacteria that makes the tomato rotten. One day, a farmer received a phone call from a scientist, that had a way to prevent this things happen. Bacterial Spot causes yield loss in tomato through reduced photosynthetic capacity and defoliation.
Fruit quality is reduced indirectly due to sun-scald and directly by bacterial lesions. Bacterial spot of tomato is caused by as many as four species of Xanthomonas, including Xanthomonas euvesicatoria, X. vesicatoria, X. perforans, and X. gardneri (reviewed by Jones et al.
, 2004).In addition, at least five physiological races—T1–T5—are recognized on the basis of a hypersensitive (HR) reaction on a differential series of host genotypes (reviewed by Robbins et al. , 2009). Descriptions of bacterial spot may use the species names, taxonomic groups A–D, or race designations. Several sources of resistance to bacterial spot have been identified. In most cases, the resistance is race specific as opposed to race non-specific (reviewed by Robbins et al.
, 2009). At any one time, a grower's field can host multiple races of Xanthomonas.Therefore, developing resistant tomato varieties will require combining resistance to multiple Xanthomonas races, through a process referred to as trait pyramiding or gene pyramiding. Techniques Phenotyping is a term used to describe inheritance studies designed to measure differences in observed plant characteristics (resistance or susceptibility to bacterial spot, in this case).
Two methods for inoculating tomato plants are typically used when evaluating—or phenotyping—germplasm for resistance to bacterial spot. Evaluation of field infections are based on the Horsfall–Barratt (1945) rating system.The scale is designed to compensate for human error in interpretation of the percentage of foliage infected. Small differences are easier to discriminate at the extremes of the scale, so the range of values for low infection and high infection percentages are narrow.
In the middle of the scale, where it is more difficult to assess small differences, the range is larger. In contrast, greenhouse evaluations are based on a qualitative assessment (resistant or susceptible) of the hypersensitive response (HR). Due to the nature of the data obtained in greenhouse vs. field trials (qualitative vs. uantitative data), data from these trials must be analyzed using different methods.
For greenhouse data, non-parametric statistical methods are appropriate, while parametric methods are often appropriate for analyzing field data. However, the data analysis method also depends on the population structure (discussed below). The germplasm tested might be that already found in the breeder's collections, or germplasm studied and results published in peer-review research articles and or germplasm databases. After the scientist put the selective breeding technology to agriculture, it helps the farmer to reduce more tomato than before.
The selective breeding tomato wont rotten, that makes the farmer’s in come higher. The selective breeding tomato helps the farmers to increase their in come and decrease their out come in the same time. The selective breeding tomato seeds’ cost is similar to normal seeds’ cost. And the restaurant’s turnover rate increase, for the vegetarians. They will always go to that restaurant for the selective breeding foods.
Like vegetables , tomatoes, potatoes etc… Reference: http://en. wikipedia. org/wiki/Selective_breeding www. youtube. com
