Psychosocial Factors on Faba Bean Yield: Effect

¶ … psychosocial factors on Faba bean yield: Effect of drought on faba bean yield The Fababean or Vicia faba L. is now being cultivated as a commercial crop and is valuable to the cash crop segments. However the plant has issues with infestations and low yields in case of droughts and parasitic attacks. Many researches in both these aspects have shown that the yields can be increased by careful monitoring of the soil and water process and while excess water is a problem the deficit causes poor yield.

The use of genomes and selective breeding shows a way to cultivate the plant successfully in the drought climate too. Vicia faba of the family Leguminosae is an annual herb with coarse and upright stems; un branched 0.3-2 m tall, with 1 or more hollow stems from the base and is found naturally in the Central Asia, Mediterranean, and South America. (Muehlbauer; Tullu, 1997) It is a shrub with vast economic value and is food for humans and domestic animals and the plant has commercial importance.

Therefore there is a large concern regarding the commercial cultivation of the crop. Faba Bean Yield -- Psychosocial Factors The major researches and innovations in the plant has been done in Australia and that is where for the last 2 decades chickpea and faba bean have been promoted as major pulse crops and are grown during winter In the low lands the crops are cultivated using the water in the ground that is stored after rainfall in the soil.

Where the soil does not retain water especially at the higher latitudes, the winter rainfall alone sustains this crop. (Siddique; Brinsmead; Knight; Knights; Paull; Rose, 1997) Fababean or Vicia faba L. is susceptible to moisture and high temperature stresses. Normally it was believed to be unsuitable for commercial production in dry lands. However the plant showed remarkable stamina in the short-season Mediterranean-type environments south Western Australia. The plant is a prey to Fababean cv.

In an experiment in 1994 at 7 sites in Australia the plant was sown in early May to early July. The seed varied from 2.0 to 4.2 t ha?1 when sown in early May. 1995 being the driest in decades yielded 0.8 to 1.8 t ha?1 when sown in mid to late May. (Loss; Siddiquea, 1997, p. 21) The delayed sowing at a rate of 13.5 to 56.0 kg ha?1 day?1 was maintained for both the periods and all the sites.

In this experiment the observation was that the first flowers could be observed in Faba beans compared to other grain legumes and cereals. The shrub could withstand spring frosts, and extreme temperatures. It did not affect the yield and the seed yield is correlated with number of pods m?2. It was proved thus that Fababean can produce impressive the biomass and seed yield for the dry land Mediterranean-type environments and the yield do not differ from the natural habitat. The only requirement in such cases would be early sowing.

(Loss; Siddiquea, 1997, p. 22) The pulse is often cultivated in rotation and many researchers have thrown up findings of germplasm that make the plant have better disease resistance. It is noted that the Faba bean produces highest yields when sown as early as possible as stated above, and the diseases are controlled by genetic resistance or fungicide application.

(Siddique; Brinsmead; Knight; Knights; Paull; Rose, 1997) The infectors of the bean are mostly fungal like 'Ascochyta blight (Ascochyta fabae), rust (Uromyces viciae-fabae), chocolate spot (Botrytis fabae), downy mildew (Peornospora viciae) and foot rots (Fusarium spp.)' (Torres; Roman; Avila; Satovic; Rubiales; Sillero; Cubero; Moreno, 2006, p. 69) The deadly enemy is the broomrape (Orobanche crenata), a very aggressive parasitic angiosperm. Researchers are afoot to combat these problems of the shrub.

Some methods include the use of gene technology for genetic improvement and the marker technology, and Quantitative Trait Loci for selection and to facilitate better breeds. Effects of Drought: In the optimum conditions where the plant Fababeans or Vicia faba L. is native and cultivated in proper atmosphere with plenty of water in the soil produce greater vegetative growth and high yields. Thus under proper rain fed conditions, the plant grows well with proper canopy. (Minguez; Ruiz-Nogueirab; Saub, 1993, p.

437) Though soil water shortage has been identified as a major constraint in increasing fababean production, the fact that excessive water availability could cause excessive vegetative growth in indeterminate fababean has been shown in a study. The indicators were the leaf initiation, expansion and biomass production, and these were reduced by soil water deficits. In the case of experiments done in the control of plant biomass, the final biomass and total leaf area duration were shown to be related.

Thus the effects of water stress were more on canopy size than on photosynthetic efficiency. (De Costa; Dennett; Ratnaweera1; Nyalemegbe, 1999, p. 86) This indicates that it may not be suitable for the dry land agriculture. (Minguez; Ruiz-Nogueirab; Saub, 1993, p. 437) The effects of periods of drought in the process of reproductive growth of faba bean (Vicia faba L.) cv.

Using pot experiments in 1987/88 and 1988/89 in China showed that the "Photosynthetic rate, chlorophyll content, leaf area, stomatal pore breadth, biomass and seed yield were decreased by all drought treatments, but stomatal frequency and respiratory rate were increased." (Xiaa, 1994, p. 68) The seed yield in the experiment reduced by c. 45% in 1987/88 and by c. 43% in 1988/89 and thus it was established that the D4 stage of reproductive development most sensitive to soil drought in the faba bean.

Though the individual researchers have shown that yields can be satisfactory if the plant is grown in dry lands, yet the major results of a number of researches show that the plant is not an efficient choice to be grown commercially for dry lands. Mainly in the plants from the dry conditions the seed yields are low and this is caused by the water stress.

The water stress occurs at the early podding stage and the water deficit at this stage will result in a drop of the seed yields of at least 50% in all three genotypes. (Mwanamwenge; Loss; Siddique; Cocks, 1999, p. 8) Conclusion It has been established that the infestations and low yields in case of droughts and parasitic attacks can be controlled by careful monitoring of the soil and water process.