All eight isolines of three maturity genes (E(1)/e(1), E(2)/e(2), and E(3)/e(3)) of soyabean [Glycine max (L.) Merrill] cv. Clark were grown in widely different combinations of photoperiod and temperature. Under the more inductive conditions, i.e. in a warm mean temperature (30 degrees C) when daylengths were less than the critical value (i.e. less than about 13 h), the isolines flowered at similar times (23-24 d). The responses of all isolines to temperature were also similar, if not identical. Increase in daylength above the critical photoperiod progressively delayed flowering until the time taken to flower (f) reached a maximum at the ceiling photoperiod. The relations between the rate of progress towards flowering (1/f) and photoperiod (between the critical and ceiling values) were linear. The coefficient characterizing the slope of the response (photoperiod sensitivity) varied amongst the isolines. These responses could be grouped into three categories of increasing sensitivity: (1) least sensitive, e(1)e(2)e(3), e(1)E(2)e(3), e(1)e(2)E(3); (2) intermediate, E(1)e(2)e(3), e(1)E(2)E(3), and (3) most sensitive, E(1)E(2)e(3), E(1)e(2)E(3), E(1)E(2)E(3). Thus, in the Clark cultivar genetic background, E(1) induces greater photoperiod sensitivity but neither E(2) nor E(3) on their own have any effect. However, both E(2) and E(3) together induce photoperiod sensitivity comparable to that induced by E(1) alone. Furthermore, in addition to this epistasis, either E(2) or E(3) has considerable epistatic effect on E(1), further increasing photoperiod sensitivity. The effects of these genes and their epistasis were also reflected in the extent of the maximum delays to flowering which occur when the ceiling photoperiod is exceeded, and also possibly in earliness in circumstances when photoperiods were below the critical value.

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In soyabean [Glycine max (L.) Merrill] the period between sowing and flowering is comprised of three successive developmental phases--pre-inductive, inductive and post-inductive--in which the rate of development is affected, respectively, by temperature only, by photoperiod and temperature, and then again by temperature only. A reciprocal-transfer experiment (carried out at a mean temperature of 25 degrees C) in which cohorts of plants were transferred successively between short and long photoperiods and vice-versa showed that eight combinations of three pairs of maturity alleles (E(1)/e(1), E(2)/e(2), E(3)/e(3)) had their greatest effect on the duration of the inductive phase in long days. This phase was increased with the increasing photoperiod sensitivity induced by the different gene combinations, and ranged from about 27 to 54 d according to genotype. In a short day regime (11.5 h d(-1)), less than the critical photoperiod, the duration of the inductive phase was brief-requiring about 11 photoperiodic cycles in the less photoperiod-sensitive genotypes and only about seven cycles in the more sensitive ones. The maturity genes also affected the duration of the two photoperiod-insensitive phases; these durations were positively correlated with the photoperiod-sensitivity potential of the gene combinations. The largest effect was on the pre-inductive phase which varied from 3 to 11 d, while the post-inductive phase varied from about 13 to 18 d. As a consequence of these nonphotoperiodic effects of the maturity genes, even in the most inductive regimes (daylengths less than the critical photoperiod) the time taken to flower by the less photoperiod-sensitive combinations of maturity genes was somewhat less than in the more sensitive combinations-ranging from about 28 to 34 d. The genetic and practical implications of these findings are discussed.

Background: Pigeonpea [Cajanus cajan (L.) Millsp.] is an important deep-rooted pulse crop, predominantly cultivated in rainfed areas by both Indian and South African countries by small and marginal farmers. Incidentally, this group of farmers are malnourished and socio-economically backward.Methods: A low input technology-‘Jawahar model for doubling income of resource constrained marginal farmers’ was evaluated once again with different combination of soil microbes in a substrate filled in used Polypropylene bags.Conclusion: Total C. cajan seed yield per plant in 3 hand pickings varied from 1066.66g to 1254.83g in different treatment combination of soil microbes in a substrate. Lac- the next produce, from the plant varied from a mean of 327.47g to 386.07g per C. cajan plant. Two premium crops from the same plant with same effort and resources per unit area may help C. cajan growers to double their income, improve their household nourishment as well as soil nutrient status.

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