6 results for Ayaz, S.

  • Variability in yield of four grain legume species in a subhumid temperate environment. II. Yield components

    Ayaz, S.; McKenzie, B.; Hill, G.; McNeil, D.

    Journal article
    Lincoln University

    The effects of plant population (one-tenth of the optimum to four times the optimum populations in 1998/99 and 10–400 plants/m² in 1999/2000) and sowing depth (2, 5 and 10 cm) on yield and yield components of four grain-legumes (Cicer arietinum, Lens culinaris, Lupinus angustifolius and Pisum sativum) were studied. Seed yields were strongly positively correlated with the number of pods and seeds/m² in both years in all species. The mean seed weight and number of branches/plant were inversely related to plant population. There was a nearly six-fold reduction in the number of branches/plant as plant population increased, which was due to restricted branching, and not to branch senescence. Generally, the variation in yield components was species dependent. However, for all species the number of pods/m² and seeds/m² could be used as primary criteria for selection in a breeding programme.

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  • Population and sowing depth effects on yield components of grain legumes

    Ayaz, S.; McNeil, D.; McKenzie, B.; Hill, G.

    Conference Contribution - Published
    Lincoln University

    Desi chickpeas (Cicer arietinum), lentils (Lens culinaris), narrow leafed lupins (Lupinus angustifolius) and field peas (Pisum sativum) were sown at three plant populations (10, 100 and 400 plants/m²) and three depths (2, 5 and 10 cm) at Lincoln University during 1999/2000. Lupins produced the most total dry matter (TDM) (972 g/m²) and lentils the least (468 g/m²). As there was relatively little variation in harvest index (HI) (0.54, lupin; 0.61, lentil), seed production followed a similar trend to TDM and ranged from 293 g/m² in lentil to 527 g/m² in lupin. There were a number of significant interactions. Pods/plant was the most variable yield component. It fell rapidly as plant population increased.

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  • Variability of harvest index in four grain legume species

    Ayaz, S.

    Thesis
    Lincoln University

    Grain legumes have the potential to be high yielding crops in Canterbury. However, like most grain legumes the problem of harvest index (HI) variability in Cicer arietinum, Lens culinaris, Lupinus angustifolius and Pisum sativum hinders the realisation of their full potential yield. In 1998/99, the four species were sown at four populations, viz. lentils cv. Rajah (15, 150, 300 and 600 plants m⁻²), desi chickpeas (5, 50, 100 and 200 plants m⁻²), lupins cv. Fest and field peas cv. Beacon (10, 100,200 and 400 plants m⁻²). In 1999/2000, all species were grown at the same three plant populations (10, 100 and 400 plants m⁻²) and at three sowing depths (2, 5 and 10 cm). Also a central plant was treated with N surrounded by other four plants to determine neighbouring plant effects, under ideal conditions. Agronomic and physiological parameters were measured to identify the causes of HI variability in grain legumes in relation to season, different populations, sowing depths and N application. Seed yield depended on the interaction between species and plant population, and species and sowing depth at harvest maturity. The highest potential seed yield of > 6.5 t ha⁻¹ in chickpeas and lupins, and about 4.5 t ha⁻¹ in lentils and peas was recorded at the higher plant populations. Seed yield was doubled at the higher populations compared to the lowest population. Trends were similar for total dry matter (TDM) production. The increase in seed yield due to population was a function of greater TDM production, crop HI (CHI), pods m⁻² and mean seed weight. The CHI values were variable and ranged from 0.31 to 0.66 over species and populations across seasons. Averaged over both seasons, the CHI was 0.59 in lentils and 0.49 in lupins, while chickpeas and peas were intermediate with 0.54 and 0.56, respectively. Sowing depth contributed less to variation in yield and yield components. Seed yield and CHI were strongly correlated both seasons. The number of pods m⁻² was the major yield component and correlated nearly perfectly with seed yield and CHI in both trials. Green area index (GAI), intercepted radiation (Fᵢ) radiation use efficiency (RUE) and total seasonal intercepted PAR significantly (P < 0.001) increased with increased plant population. Lupins produced the greatest maximum biomass and intercepted more radiation than the other three legumes. In all species in both trials the highest populations reached their peak GAI about 7 - 10 days earlier than the low populations. The cumulative intercepted PAR had significant and positive association with seed yield and CHI. The RUE varied widely within and among species and populations. The RUE increased as plant population increased and was highest in the greatest yielding legume species. However, RUE was inversely related to the extinction coefficient (k) and was strongly associated with CHI. The relationships among individual plants were studied to quantify the influence of neighbouring plants using the principal axis model (PAM). The PAM was based on a principal axis, which represented the linear relationship (r²> 0.90) between SWT and PWT. A negative SWT-axis intercept was confirmed for each species in this study. Both mean SWT and PWT were inversely related to plant population. Yield, yield components and plant HI (PHI) were decreased significantly in the southerly plant compared with the N treated and with control plants. The PAM took into account the performance of individual plants and identified the variability and lowest or highest yielding plants. The relationship between PHI and PWT was asymptotic. The minimum plant weight (MPW) was species dependent and was highest for plants grown at the lowest population and decreased with increased population. In all four species N concentration was highest in seed followed by senescent leaves, while the lowest level was in straw. Lupins produced the greatest amount of seed N (16.82 and 19.29 g m⁻²) followed by chickpeas (10.26 and 13.10 g m⁻², during 1998/99 and 1999/2000, respectively). Lentils had the lowest N concentrations and yield in this study. The distribution of N to different parts of legumes increased with increased population. Averaged over all populations, the NHI was stable in each species across the two seasons. However, it changed with changed population and sowing depth. The N accumulation efficiency (EN) was highest in lentils (0.024 and 0.027 g N g⁻¹ DM) and lowest in chickpeas (0.018 and 0.021 g N g⁻¹ DM) in 1998/99 and 1999/2000, respectively. The NHI and the CHI were correlated and both were strongly associated with seed yield.

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  • Nitrogen distribution in four grain legumes

    Ayaz, S.; McKenzie, B.; Hill, G.; McNeil, D.

    Journal article
    Lincoln University

    The partitioning of above ground nitrogen (N) in chickpea (Cicer arietinum), lentil (Lens culinaris), lupin (Lupinus angustifolius) and pea (Pisum sativum) at crop maturity was investigated. The plants were grown at different plant populations and sowing depths in 1998/99 and 1999/2000 in Canterbury, New Zealand. In all four legumes the N concentration was highest in seed (29–36 mg/g N) followed by senescent leaves. The lowest N concentration was in stems. Lupin had the highest seed N yield at 16·82 and 19·29 g/m² followed by chickpea at 10·26 and 13·10 g/m², in 1998/99 and 1999/2000, respectively. Lentil had the lowest N concentrations and yield. The distribution of N to all legume plant parts increased as population increased up to twice the optimum and 400 plants/m² in 1998/99 and 1999/2000, respectively. Over all plant populations, the nitrogen harvest index (NHI) was stable in each of the four species across the two seasons. However, the NHI changed with changes in plant population and sowing depth. The N accumulation efficiency (EN) was highest in lentil at 0·024 and 0·027 g N/g DM and lowest in chickpea at 0·018 and 0·021 g N/g DM in 1998/99 and 1999/2000, respectively. The NHI and the crop harvest index (CHI) were correlated and both were strongly associated with seed yield. Thus, NHI might be useful as a selection criterion to improve seed yield in grain legumes.

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  • Variability in yield of four grain legume species in a subhumid temperate environment. I. Yields and harvest index

    Ayaz, S.; McKenzie, B.; Hill, G.; McNeil, D.

    Journal article
    Lincoln University

    In 1998/99 and 1999/2000, field trials were conducted to try to explain why grain legume yields and harvest index are more variable than many other crops. Treatments involved varying plant populations and sowing depths and were selected to maximize plant variability. Both yields and harvest index were variable. Total dry matter (TDM) production generally increased as plant population increased up to twice the optimum population. Increases ranged from 80 to 130% with lupins producing the highest yields of 878 and 972 g/m² of TDM in 1998/99 and 1999/2000 respectively. While plants sown at 10 cm depth produced more TDM than did plants sown at 2 cm, the difference was only 3%. Seed yields followed similar trends to TDM, with maximum yields (mean of 403 g seed/m²) produced at twice the optimum population. Crop harvest index (CHI) was quite variable and ranged from 0·31 to 0·66. Crop HI was lowest (0·43) at the lowest population and increased to 0·55 at twice the optimum plant population. In both seasons, lentil had the highest CHI and lupin the lowest. While CHI was variable there were very close relationships between seed yield and TDM which suggested that maximum seed yield depends on maximizing TDM production. The results also suggest that growers should increase population by a factor of two to obtain maximum seed yields.

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  • Light interception and utilization of four grain legumes sown at different plant populations and depths

    Ayaz, S.; McKenzie, Bruce A.; McNeil, D.; Hill, George D.

    Journal article
    Lincoln University

    Canopy development, radiation absorption and its utilization for yield was studied in four grain legume species Cicer arietinum, Lens culinaris, Lupinus angustifolius and Pisum sativum. The grain legumes were grown at different plant populations and sowing depths over two seasons in Canterbury, New Zealand. The green area index (GAI), intercepted radiation, radiation use efficiency (RUE) and total intercepted photosynthetically active radiation (PAR) increased significantly (P<0·001) with increased plant population. Narrow-leafed lupin produced the highest maximum biomass (878 and 972 g/m², averaged over all populations during 1998/99 and 1999/2000, respectively) and intercepted more radiation (600 and 714 MJ/m², averaged over all populations during 1998/99 and 1999/2000, respectively) than the other three legumes. In all four species, in both trials, the highest plant populations reached their peak GAI about 7–10 days earlier than legumes sown at low populations. Cumulative intercepted PAR was strongly associated with seed yield and crop harvest index (CHI). The RUE increased (from 1·10 to 1·46 and from 1·04 to 1·34 g/MJ during 1998/99 and 1999/2000, respectively) as plant population increased and was highest in the highest yielding species (e.g. 146 and 1·36 g/MJ for narrow-leafed lupin in both experiments). The larger leaf canopies produced at the higher plant populations reduced the extinction coefficient (k). The results suggest that in the subhumid temperate environment of Canterbury, grain legume species should be selected for the development of a large GAI. This should maximize PAR interception, DM production and, consequently, seed yield.

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