scholarly journals Mejoramiento genético del frijol rojo y negro mesoamericano para Centroamérica y El Caribe.

2006 ◽  
Vol 11 (2) ◽  
pp. 37 ◽  
Author(s):  
Juan C. Rosas ◽  
Aracely Castro ◽  
Edwin Flores
Keyword(s):  
Central America ◽  
Economic Value ◽  
Low Fertility ◽  
Major Market ◽  
Marginal Areas ◽  
Abiotic Constraints ◽  
Selection For ◽  
Web Blight ◽  
On Farm ◽  
Great Portion

Bean production in Central America is mainly a small farm operation on hillside, marginal areas, limited by several biotic and abiotic constraints. More than 350,000 t of beans are produced in nearly 0.5 millions of hectáreas, with a rather low yield average of 678 kg/ha. The majority of bean producers utilize low inputs and few farms are mechanized. Autoconsumption is rather high; however, a great portion of the beans is sold by intermediaries. In Honduras, beans are the 7th most important crop in economic value, and has the highest economic return among corn, rice and sorghum. The major market classes in Central America are small red and black (race Mesoamerican) beans. Improvement of these bean types is focused in developing resistance to diseases (common mosaic, golden mosaic, anthracnose, angular leaf spot, rust, web blight, and common bacterial blight) and pests (mainly pod weevil); and tolerance to low fertility, drought and heat. Appropriate hybridization and selection programs are utilized for developing multiple resistant, high yielding, well adapted and commercially accepted cultivars. A broad genetic base is accomplished by using Andean and Mesoamerican sources of germplasm in the hybridization stage. Simultaneous selection for various traits and multilocation testing of advanced lines are practiced. Yield and adaptation nurseries and trials of improved lines are distributed to Central America, Mexico, Panama and Caribbean countries. Testing of advanced lines and on-farm validation and varietal release, are carried out by National Bean Programs and institutions, members of the PROFRIJOL regional program, in collaboration with Zamorano, CIAT and the Bean/Cowpea CRSP.

ON-FARM FORESTRY DEVELOPMENT OPTIONS FOR NORTHLAND

1986 ◽  
pp. 27-32
Author(s):  
J.S. Clark
Keyword(s):  
Joint Ventures ◽  
Low Fertility ◽  
High Fertility ◽  
Financial Returns ◽  
Farm Forestry ◽  
Hill Country ◽  
Financial Position ◽  
On Farm

Agroforests and woodlots offer Northland hill country farmers investment and diversification opportunities. Agroforests have less effect on the "whole farm" financial position than woodlots, especially where a progressive planting regime is adopted and where no further borrowing is required. Establishment and tending costs for agro-forests are lower, and returns come much sooner. The proven opportunity for continued grazing under trees established in this manner, apart from a short post-planting period, further enhances the agroforesty option. Even where there is reluctance on a farmer's part to plant trees on high fertility land, the expected financial returns from agroforests on low and medium fertility land will increase the overall long-term profitability and flexibility of the whole farming operation. Woodlots may be more appropriate on low fertility areas where weed reversion is likely. Joint ventures may be worth considering where farm finances are a limited factor. Keywords: On-farm forestry development, Northland hill country, agroforestry, woodlots, diversification, joint ventures, progressive planting regimes, grazing availability.

FERTILITY OF BARLEY AUTOTETRAPLOIDS: I. FERTILITY IN SUCCESSIVE GENERATIONS OF FOUR AUTOTETRAPLOID BARLEY VARIETIES AND THE EFFECT OF SELECTION FOR FERTILITY IN THE O.A.C. 21 AUTOTETRAPLOID

1959 ◽  
Vol 39 (1) ◽  
pp. 98-107 ◽  
Author(s):  
E. Reinbergs ◽  
L. H. Shebeski
Keyword(s):  
Promising Method ◽  
Low Fertility ◽  
Fertility Level ◽  
Seed Setting ◽  
The Mean ◽  
Selection For ◽  
Successive Generations ◽  
Subsequent Selection

The differences in fertility of four colchicine-induced autotetraploid barley varieties (Brant, Montcalm, O.A.C. 21 and York) were determined and compared in four successive generations following the induction of tetraploidy. Despite a wide fertility range within each autotetraploid, the varieties tested varied considerably in their mean per cent fertility. Within each variety the mean per cent fertility remained relatively constant from generation to generation. The Montcalm tetraploid had the lowest mean fertility, fluctuating from generation to generation within a range of 6.0 to 10.1 per cent. The O.A.C. 21 tetraploid had the highest mean fertility, fluctuating within a range of 40.0 to 51.3 per cent.Significant differences in fertility of the four autotetraploid varieties were interpreted as indicating that seed-setting ability may be genetically controlled and, therefore, hybridization and subsequent selection could be a promising method for increasing fertility.Continuous selection for either high or low fertility from the C1 to C4 generation did not change the mean per cent fertility level in the O.A.C. 21 tetraploid.

scholarly journals Leaf Transcriptome Assembly of Protium copal (Burseraceae) and Annotation of Terpene Biosynthetic Genes

Genes ◽  
2019 ◽  
Vol 10 (5) ◽  
pp. 392
Author(s):  
Gabriel Damasco ◽  
Vikram S. Shivakumar ◽  
Tracy M. Misciewicz ◽  
Douglas C. Daly ◽  
Paul V. A. Fine
Keyword(s):  
Central America ◽  
Transcriptome Assembly ◽  
Economic Value ◽  
Biosynthetic Genes ◽  
Genomic Resources ◽  
Phylogenetic Studies ◽  
Leaf Transcriptome ◽  
Aromatic Components ◽  
Medicinal Properties ◽  
Large Distribution

Plants in the Burseraceae are globally recognized for producing resins and essential oils with medicinal properties and have economic value. In addition, most of the aromatic and non-aromatic components of Burseraceae resins are derived from a variety of terpene and terpenoid chemicals. Although terpene genes have been identified in model plant crops (e.g., Citrus, Arabidopsis), very few genomic resources are available for non-model groups, including the highly diverse Burseraceae family. Here we report the assembly of a leaf transcriptome of Protium copal, an aromatic tree that has a large distribution in Central America, describe the functional annotation of putative terpene biosynthetic genes and compare terpene biosynthetic genes found in P. copal with those identified in other Burseraceae taxa. The genomic resources of Protium copal can be used to generate novel sequencing markers for population genetics and comparative phylogenetic studies, and to investigate the diversity and evolution of terpene genes in the Burseraceae.

The improvement of crop yield in marginal environments using 'on-farm' seed priming: nodulation, nitrogen fixation and disease resisitance

2005 ◽  
Vol 56 (11) ◽  
pp. 1211 ◽  
Author(s):  
D. Harris ◽  
W. A. Breese ◽  
J. V. D. K. Kumar Rao
Keyword(s):  
Field Experiments ◽  
Low Cost ◽  
Seed Priming ◽  
Plant Performance ◽  
Individual Plant ◽  
Rhizobium Inoculation ◽  
Marginal Areas ◽  
Resource Poor ◽  
On Farm

On-farm seed priming with water is a low-cost, low-risk technology that is easily adopted by resource-poor farmers. It increases the yield of tropical and subtropical annual crops in marginal areas by a combination of better crop establishment and improved individual plant performance. The effects of seed priming, i.e. soaking seeds overnight in water before sowing, on plant growth and development are consequences of faster germination, emergence, and more vigorous early growth. Results from in-vitro, on-station and on-farm experiments are discussed. Recent work has tested opportunities for resource-poor farmers to use seed priming as a vehicle for applying biofertilisers (Rhizobia). Preliminary results from field experiments suggest that these interventions are very effective over and above the already demonstrated benefits of priming with water alone. In a pot experiment using chickpea, combining a Rhizobium inoculation with seed priming significantly increased nodulation but had little effect on yield. Nevertheless, the results confirmed that Rhizobium inoculation is compatible with on-farm seed priming. Observations in the field have shown that some primed crops show enhanced resistance to disease, either as a consequence of increased vigour, altered phenology, or due to some more fundamental mechanism associated with exposure of seeds to anaerobic conditions during priming. Priming seeds of a highly susceptible cultivar of pearl millet in water for 8 h before sowing significantly reduced the incidence of downy mildew in artificially infected seedlings from 80% to less than 60%.

Index selection for improved growth and carcass characteristics in a population of Large White pigs

1988 ◽  
Vol 46 (2) ◽  
pp. 265-275 ◽  
Author(s):  
M. Ellis ◽  
J. P. Chadwick ◽  
W. C. Smith ◽  
R. Laird
Keyword(s):  
Carcass Characteristics ◽  
Live Weight ◽  
Conversion Ratio ◽  
Index Selection ◽  
Food Conversion ◽  
Genetic Progress ◽  
Large White ◽  
Selection For ◽  
On Farm ◽  
Ad Libitum Feeding

AbstractAn experiment was carried out over 11 years to investigate selection for economy of production and carcass lean content under ad libitum feeding in Large White pigs. Two lines, a selection (S) and a control (C) line, were involved in the study. The S line comprised 80 females and 10 males and was based at two centres. Boars were performance tested centrally at one of the centres and gilts were on-farm tested. Testing was carried out in groups of two or three full-sibs over the live-weight range 27 o t 87 kg. Selection was based on an index (I) incorporating individual daily live-weight gain (DLWG) and ultrasonically measured backfat thickness (USBF) and a group food conversion ratio (FCR) and generations were overlapping. The C line (32 females and 16 males) was maintained at one centre and males were performance tested alongside S boars to monitor genetic progress. Cumulative realized selection differentials over years 1 to 10 were equivalent to 5·5, 51, 7·0 and 9·4 phenotypic standard deviations for DLWG, USBF, FCR and I respectively and generation intervals averaged 17·0 months. There was little genetic change in DLWG, however, USBF, FCR and I showed substantial improvements with cumulative responses in year 11 of —12·3 mm, —0·22 kg/kg and +45·2 points respectively. The reduction in USBF occurred in the first half of the study with no further improvements being achieved after year 6. This study illustrates the effectiveness of index selection for a limited number of economically important traits but highlights limitations to this approach.

PARTICIPATORY EVALUATION BY FARMERS OF ON-FARM SEED PRIMING IN WHEAT IN INDIA, NEPAL AND PAKISTAN

2001 ◽  
Vol 37 (3) ◽  
pp. 403-415 ◽  
Author(s):  
D. Harris ◽  
B. S. Raghuwanshi ◽  
J. S. Gangwar ◽  
S. C. Singh ◽  
K. D. Joshi ◽  
...  
Keyword(s):  
Seed Priming ◽  
Germination Percentage ◽  
Wheat Seed ◽  
Saline Irrigation ◽  
Yield Increase ◽  
Marginal Areas ◽  
Input Use ◽  
On Farm ◽  
Tribal Areas ◽  
Mean Time

The mean time for 50% germination at 20 °C of 12 Indian wheat (Triticum aestivum) cultivars was nearly halved, from 51 h to 27 h, by soaking seed in water for 8 h prior to sowing. A delay of 24 h without further soaking, intended to simulate postponement of sowing, reduced the time saved by priming to 16%. Priming had no effect on final germination percentage. These results were used in the design of 275 on-farm, farmer-managed, participatory trials of seed priming in wheat during the 1997–98 and 1998–99 rabi (post-monsoon) seasons. In forty-one trials in tribal areas of Bihar and West Bengal states of India, seed priming gave a 13% grain yield advantage for farmers growing wheat in marginal areas with low levels of agricultural inputs. Mean benefits from seed priming of wheat in nine trials in Chitwan, Nepal were 17%. In high potential areas of Gujarat, India, 205 trials had higher rates of input use. Yield benefit from priming in these trials averaged only 5% but constituted an extra 200 kg ha−1 grain at little or no cost. In 20 trials on marginal land, with slightly saline irrigation water in Ahmadwala, Pakistan, an average yield increase of 36% was obtained using seed primed with a 0.2% gypsum solution. Collaborating farmers reported that priming wheat seed overnight resulted in faster, more complete emergence, more vigorous early growth, better tillering, earlier flowering, larger ears, earlier maturity and higher yields. In addition, many farmers also reported that foliage in primed plots was a darker shade of green than that in non-primed plots, suggesting that primed plants may have been using nitrogen more efficiently. Seed priming was popular with farmers, most of whom reported that they would prime wheat seed the following year. A survey in Gujarat in 1998–99 of 63 farmers who had tested priming in 1997–98 showed that, while 65% had primed some of their own seed, none had primed more than 50 kg, suggesting that there were practical difficulties in priming larger volumes of seed.

scholarly journals Aplikasi Indigenous Microorganism (Em-4) dan Pupuk Kompos Terhadap Pertumbuhan dan Produksi Tanaman Cabai Merah (Capsicum annum L.) pada Tanah Ultisol

2019 ◽  
Vol 1 (2) ◽  
pp. 114
Author(s):  
Ratna Shanti
Keyword(s):  
Economic Value ◽  
Fruit Yield ◽  
Low Fertility ◽  
Growth And Yield ◽  
Quadratic Regression ◽  
Indigenous Microorganism ◽  
Compost Application ◽  
Main Plot ◽  
The Relationship ◽  
Plot Design

Red Chilli is commodity of vegetable that has high economic value, but still has slow productivity. The objective of this study was identify the effect of indigenous microorganism (EM 4) application and compost to increased the growth and yield of Red Chilli Plant (Cappcicum annum L) on Ultisol. Field trial was conducted on Ultisols in Horticulture Experimental Station, BatuahLoajanan, Kutai Kartanegara. The soil was characterized by low fertility status. The amount of organic matter and microbial acivity are very low. This trial was started on January until April 2017 using Split Plot Design with three replications Main plot consisted of two levels treatment i.e. without EM-4 (E0) as control and Effective Mikroorganisms-4 (E). Sub-plot was four rates of organic compost i.e. 0, 10, 20 and 30 tons ha-1 and chili was used as test plant.Results indicated that EM-4 treatment showed a significant effect on fruit yield of chilli. It increased the fruit yield 38 percent compare to control. Compost application significantly increased on fruit yield. The relationship between unfermented compost rate and fruit yield shows a linear regression YE0 = 1.699 + 0.047 X (r = 0.95) and quadratic regression for EM-4 fermented compost YE1 = 1,175 + 0,319 X – 0.007 X2(R2 = 0.603). Optimum compost rate was 23 ton.ha-1.To increased fruit yield of chilli, EM-4 fermented compost should be applied into and it can decreased compost rate application.

scholarly journals Optimizing Selection for Yield Using Selection Index

Zuriat ◽  
2015 ◽  
Vol 13 (1) ◽  
Author(s):  
Sugiono Moeljopawiro
Keyword(s):  
Selection Index ◽  
Economic Value ◽  
Selection Procedure ◽  
Panicle Length ◽  
Diallel Crosses ◽  
Individual Trait ◽  
Selection Indices ◽  
Selection For ◽  
Grain Width ◽  
Half Diallel

An experiment was conducted to construct selection indices for yield. F2 populations of half diallel crosses involving six cultivars were analyzed to calculate phenotypic and additive genetic variances and covariances which were used to construct selection indices. Results of the selection index indicated that selection applied to several traits simultaneously was more efficient than selection based on an individual trait or a combination of only one or two traits. However, the choice of traits to be included in a selection index should be determined by their economic value and Index involving panicle length, grain length, and grain width, was a promising index in this study. A selection index properly constituted can be used to improve the selection procedure, once homozygousity is assured.

scholarly journals 215 Selection response for meat quality and carcass composition in commercial pigs using crossbred and purebred traits as predictors

2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 45-45
Author(s):  
Emmanuel A Lozada-Soto ◽  
Justin Fix ◽  
Clint Schwab ◽  
Francesco Tiezzi
Keyword(s):  
Meat Quality ◽  
Lower Cost ◽  
Economic Value ◽  
Cost Effective ◽  
Selection Response ◽  
Carcass Composition ◽  
Direct Selection ◽  
Selection Indices ◽  
Breeding Objectives ◽  
Selection For

Abstract Meat quality (MQ) and carcass composition (CC) are traits with high economic value, but their phenotyping costs makes direct selection for these traits economically unsustainable. Evaluation of traits with lower cost of collection in crossbred (CB) and purebred (PB) animals for use in selection for MQ and CC remains limited. The aim of this study was to measure the response to selection of economically important MQ and CC traits using different selection indices built on cost-effective correlated traits. Phenotypic and genomic information (using 60K SNP chips) was collected for three-way CB (n = 1227 to 5117 phenotyped, n = 1252 genotyped) and PB (n = 3,251 phenotyped, n = 1035 genotyped) Duroc animals belonging to 28 paternal half-sib families. The three breeding objectives (for which response was estimated) were intramuscular fat (IMF), slice shear force (SSF), and loin weight (LW). In total 7 different selection indices (A-G) were used to estimate the selection response for each breeding objective (Table 1). Heritability and genetic correlation parameters for all traits were estimated using GIBBS1F90. Selection response was obtained as expected response per generation weighed by the accuracy of breeding values estimated from a 4-fold cross validation, where animals were grouped based on sire relatedness. For all three breeding objectives, the index which provided best selection response was A (direct selection), with values of 0.35%, -0.72 kg, and 0.85 kg for IMF, SSF, and LW respectively. The index which provided the second-best selection response was B (color and pH traits) for all three breeding objectives, with values of 0.15%, -0.26kg, and 0.30kg for IMF, SSF, and LW respectively. Results for selection response using indices C-G can be found in Table 1. In the absence of direct selection due to high costs of phenotyping, respectable selection response can be achieved by indirect selection using traits with lower cost of collection.

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