5. The Extent and Rate of Adoption of Modern Cultivars in India

Witcombe, J. R.; Packwood, Andrea; Virk, D. S.; Raj, A G B

doi:10.3362/9781780445854.005

Cited by 21 publications

(25 citation statements)

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“…The literature on the issue of variety adoption is very rich, suggesting that in general, it is very difficult during the breeding program to predict whether or not the varieties will be adopted. This is in part because in a conventional system, 5 to 6 yr typically pass after official release before appreciable adoption commences (Morris et al, 1992; Witcombe et al, 1998), and during this time, farmers’ priorities, agronomic conditions (e.g., availability of irrigation or fertilizer price), policy measures (e.g., introduction or removal of subsidies), and market demands may change, making the breeding objectives set at the beginning of the breeding program obsolete.…”

Section: Measures Of Plant Breeding Efficiencymentioning

confidence: 99%

Efficiency of Plant Breeding

Ceccarelli¹

2015

Crop Science

157

124

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Participatory plant breeding (PPB) has been practiced for several reasons, including sociological, humanitarian, and egalitarian. This paper aims to demonstrate that PPB should be practiced simply because it increases plant breeding efficiency, which is defined as (i) the ratio between the number of varieties adopted and the number of crosses made, (ii) the response to selection, and (iii) the benefit/cost ratio, not only as often done by public breeding programs, by the number of varieties released by public breeding programs. After reviewing the reasons for the lack of adoption of several of the varieties released, and the theoretical basis justifying the use of correlated response to measure selection gains, the issue of the benefit/cost ratio is discussed within the context of adoption rates. The assumption is that without adoption, no benefit will occur. Ways to increase the three measures of breeding efficiency are discussed in detail, and the conclusion is made that the three measures can be increased by combining decentralized selection with farmers’ participation in a PPB program. The essential features of a PPB program are reviewed, including the experimental designs and statistical analysis used to increase the precision of on‐farm trials. The findings show that PPB increases breeding efficiency, both in terms of response to selection measured over the time from the initial cross to adoption and in terms of the benefit/cost ratio as a consequence of a higher adoption rate. In a PPB program, adoption starts during the process of selection and precedes variety release. In a conventional plant breeding (CPB) program, the sequence is reversed. Other differences between a PPB and a CPB program include the increase of agrobiodiversity, which in a PPB program is higher because of the rapid spatiotemporal turnover of varieties, and because the seed of new varieties is readily available to farmers, thus contributing to food security. Because of its decentralized nature, PPB can accommodate organic farms and become easily adopted by both national and international public breeding programs as one way of adapting crops to climate changes.

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Section: Measures Of Plant Breeding Efficiencymentioning

confidence: 99%

Efficiency of Plant Breeding

Ceccarelli¹

2015

Crop Science

157

124

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“…There has been sufficient time to produce quantitative evidence on success or failure for the first four crosses and strong indications on the success of the last two. We compared the success rate of these six crosses with that in conventional breeding where success was defined as when a cross had produced at least one officially released variety – a conservative measure for the comparison as it overestimates success in the conventional programmes because a significant proportion of released varieties are never adopted [27,28]. For our breeding programme, success was defined as when a cross had produced a variety that farmers adopted (most adopted varieties were also released).…”

Section: Methodsmentioning

confidence: 99%

Plant breeding can be made more efficient by having fewer, better crosses

et al. 2013

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BackgroundCrop yields have to increase to provide food security for the world’s growing population. To achieve these yield increases there will have to be a significant contribution from genetic gains made by conventional plant breeding. However, the breeding process is not efficient because crosses made between parental combinations that fail to produce useful varieties consume over 99% of the resources.ResultsWe tested in a rice-breeding programme if its efficiency could be improved by using many fewer, but more judiciously chosen crosses than usual. In a 15-year programme in Nepal, with varietal testing also in India and Bangladesh, we made only six crosses that were stringently chosen on complementary parental performance. We evaluated their success by the adoption and official release of the varieties they produced. We then modelled optimum cross number using assumptions based on our experimental results.Four of the six crosses succeeded. This was a fifty-fold improvement over breeding programmes that employ many crosses where only about one, or fewer, crosses in 200 succeed. Based on these results, we modelled the optimum number of crosses by assuming there would be a decline in the reliability of the breeder’s prediction of the value of each cross as more crosses were made (because there is progressively less information on the traits of the parents). Fewer-cross programmes were more likely to succeed and did so using fewer resources. Making more crosses reduced the overall probability of success of the breeding programme.ConclusionsThe efficiency of national and international breeding programmes would be increased by making fewer crosses among more carefully chosen parents. This would increase the number of higher yielding varieties that are delivered to farmers and hence help to improve food security.

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“…It also meant that farmers were not benefiting from decades of plant breeding research because they were not adopting new varieties that had been released, largely because plant breeders had concentrated on yield rather than providing varieties that at least matched M35-1 for grain quality (Witcombe et al, 1998). Maldandi was released in 1930 in Maharashtra, and M35-1 was released for Maharashtra, Karnataka, and AP in 1984.…”

Section: Participatory Varietal Selectionmentioning

confidence: 99%