Summer forage legumes from the species Vigna unguiculata, Macroptilium lathyroides, Lablab purpureus, Arachis hypogaea and Glycine max were grown under irrigation at Trangie, New South Wales. Dry matter accumulation and plant development were recorded in primary growth and three subsequent regrowths. Plant fractions were analysed for nitrogen, sulfur and sodium during primary growth. In primary growth lablab produced the highest dry matter yield of 14 t/ha. This was attributed to very late flowering (110 days) and woody stems able to support this bulk. In contrast, cowpea lodged after producing 7 t/ha. Soybean produced 10 t/ha of dry matter but rapid leaf abscission detracted from its forage potential. Phasey bean was an excellent species under a 6-week cutting regime, yielding 10 t/ha from four cuts. In contrast to other species, it branched rapidly and extensively from basal buds. The basal branching and prostrate growth habit of peanut enabled it to yield 9 t/ha from three cuts. The leaves of all species contained over 3% nitrogen; mature stems had only half this concentration. Phasey bean and cowpea had much higher sodium contents (1040 and 1535 ppm at 10 weeks) than lablab (335), peanut (80), and soybean (165), the latter three being below recommended levels for animal production. All species contained satisfactory levels of sulfur (0.21, 0.30, 0.20, 0.18 and 0.17% in phasey bean, cowpea, lablab, peanut and soybean, respectively, at 10 weeks).

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Barnyard millets (Echinochloa utilis and E. frumentacea), maize (Zea mays) and a sorghum hybrid (Sorghum bicolor x S. sudanense) were grown as spaced plants at temperature regimens from 15/10 to 33/28�C (dayhight). Leaf and stem dry weight, leaf area and leaf number were recorded every 2 weeks and the dry matter analysed for nitrogen, sulfur, sodium and in vitro digestibility. Tolerance to low temperatures was in the order maize > E. utilis >sorghum >E. frumentacea. At mean temperatures above 25�C, relative growth rates were similar for all species. Differences in leaf area, for which individual leaf size was mainly responsible, accounted for most of the dry weight responses to temperature, although net assimilation rate responses were also apparent. The dry weight response to temperature became negligible after adjusting for differences in stage of development. Dry matter digestibility decreased with temperature; it also decreased with time because of deteriorating stems, except in sorghum. Maize leaves were of low digestibility, similar to stems. The nitrogen : sulfur ratio of all species remained steady with age; in sorghum at low temperature it exceeded the 15: 1 maximum considered desirable for animals. Sodium was highest in E. utilis stems and increased with temperature, in contrast to sorghum. Maize had a marginal nitrogen: sulfur ratio and unacceptably low sodium concentration. It was concluded that more attention should be given to E. utilis as a forage for cool climates.

Two cultivars of Echinochloa utilis, Ohwi et Yabuno, and one E.frumentacea (Roxb.) Link cultivar were grown in a glasshouse under three photoperiod regimes: naturally varying photoperiods (1 2-1 3 h), and fixed photoperiods of 14 and 16 h. Both species behaved as quantitative short-day plants although, in E. utilis, extending the photoperiod from 14 to 16 h delayed head emergence disproportionately. The delay in head emergence did not affect the relative growth rate, and longer photoperiods led to higher shoot weights; main tiller leaf number increased only slightly. The commencement of apical meristem elevation was delayed under longer photoperiods, a feature believed to be beneficial to regrowth. A time-of-sowing study in the field illustrated the effect of this short-day response upon crop development. Sixteen introduced E. utilis cultivars and 10 E. frumentacea cultivars also behaved as quantitative short-day plants. Within each species there were differences between cultivars in sensitivity to photoperiod. Some cultivars of E. utilis were very late and had abnormal head emergence at 16 h. Latitudinal effects on the performance of these cultivars are discussed.

White Spanish, Red Spanish and Virginia Bunch cultivars of Arachis hypogaea L. were sown at two row spacings (30 and 60 cm) and two times (29 October and 3 December) on an alkaline clay soil in western New South Wales. The crops were furrow irrigated between raised beds 1 m wide. Maximum oven dry pod yields were 3.0, 2.3 and 3.3 t ha-1 for white Spanish, Red Spanish and Virginia Bunch respectively. Corresponding shelling percentages were 65, 68 and 57%. White Spanish and Virginia Bunch matured 180-190 days after early sowing and Red Spanish after 210 days when frost stopped growth. The late sown crop failed to mature before the frosts, and yielded 15-25% less than the early sowing. The late crop had a shorter period for the production of pods and also a slightly lower rate of pod production because of reduced shoot growth; kernel weight per pod was similar at both sowings. Differences between cultivars were accounted for by differences in the rate of pod filling and hence ultimate kernel weight per pod, and furthermore, the harvest index differed among cultivars. White Spanish or Virginia Bunch sown in 30 cm rows before December can be recommended for irrigated groundnut production in western New South Wales.