Effect of environmental conditions on growth and rubber production of guayule (Parthenium argentatum)

1985 ◽  
Vol 36 (2) ◽  
pp. 285 ◽  
Author(s):  
RW Downes ◽  
ML Tonnet

Nine lines of guayule were grown in the field near Narrabri and Canberra. Rubber percentage and dry matter production were estimated after four years' growth. Although dry matter yield per plant was comparable in the two locations, the rubber content was higher at Narrabri. Rubber percentage was greater after winter than after summer, indicating that cool conditions were favourable for rubber accumulation. This was supported in phytotron studies where rubber percentage was much higher at 15/10 than 24/19�C day/night temperatures. In contrast, elongation of shoots was promoted by high temperature, high radiation conditions. In a phytotron study guayule transpired substantially less than wheat per unit leaf area. The agronomic consequences of these findings are discussed.

Crop Science ◽  
2002 ◽  
Vol 42 (1) ◽  
pp. 146 ◽  
Author(s):  
P. Q. Craufurd ◽  
P. V. Vara Prasad ◽  
R. J. Summerfield

CERNE ◽  
2017 ◽  
Vol 23 (4) ◽  
pp. 507-515 ◽  
Author(s):  
Veronica Brito da Silva ◽  
Rogerio Figueiredo Daher ◽  
Bruna Rafaela da Silva Menezes ◽  
Maria Lorraine Fonseca Oliveira ◽  
Maria do Socorro Bezerra Araújo ◽  
...  

ABSTRACT The elephant-grass undergoes successive cutting and periodical evaluations that it possible to identify clones with high stability for dry matter production, which can be used for energy production. The present study was carried out to evaluate stability dry matter yield for different parametric and non-parametric methods in elephant grass genotypes for biomass production undergoes successive cutting in the agroclimatic conditions of the Norte Fluminense (RJ, Brazil). The variable measured in the 40 genotypes was dry matter yield (DMY) at 2009, 2010 and 2011 in a field study designed as randomized block design with two replicates. Each sample was grown in different environment condition. The stability methods tested were the Yates and Cochran’s, Plaisted and Peterson’s, Wricke’s ecovalence, Annicchiarico’s, Lin and Binns’ and Kang and Phan’s. Results indicated that cutting (E) and genotypes (G) influenced significantly on the performance of dry matter yield. The non-parametric stability methods were effective for the evaluation of stability in dry matter yield. Genotypes Mercker, Pinda-México, Mercker 86-México, Guaçu/IZ, Mercker Pinda, P-241-Piracicaba and Cubano Pinda were stable stability dry matter yield. Hence, there are genotypes may be exploited in future breeding programmes in order to improve productivity of upland elephant grass over environment.


1985 ◽  
Vol 40 (2) ◽  
pp. 267-277 ◽  
Author(s):  
T. A. Stewart ◽  
I. I. McCullough

ABSTRACTSilage cut twice annually (June and August) from a tetraploid red clover/grass sward and three times annually (May, July and September) from a low nitrogen (N) and high N perennial ryegrass/white clover sward was fed in proportion to dry-matter yield from each cut, over a 10-week period, each winter for 3 years to castrated male cattle of initial live weight 401 kg in year 1 and 425 kg in years 2 and 3. The silages were supplemented with 0, 1, 2 and 3 kg concentrate per head daily.Total dry-matter yield from the red clover/grass sward was similar to that from the perennial ryegrass/white clover sward (high N grass) receiving 360 kg N per ha but the digestibility, particularly of first cut material was much lower. Dry-matter production of the low N grass/white clover sward was 0·73 of high N grass sward and produced silages of similar digestibility and fermentation.Dry-matter intakes by the cattle were higher on the legume-based silages in years when clover made a worthwhile contribution to total yield, but this did not significantly improve utilization or animal performance compared with high N grass silage. Mean daily carcass gain per head on red clover/grass silage was 0·41 kg which was significantly less than the 0·61 kg on white clover/grass silage and 0·59 on high N grass (P < 0·001). Carcass output from red clover/grass silage was 618 kg/ha and 629 kg/ha from white clover/grass, both of which were significantly less than the 863 kg/ha from the high N grass silage (P < 0·001). Dressing proportion was also significantly poorer in animals fed red clover/grass silage compared with the other silage types.


1988 ◽  
Vol 15 (6) ◽  
pp. 815 ◽  
Author(s):  
GC Wright ◽  
KT Hubick ◽  
GD Farquhar

Variation in water-use efficiency (W, g of total dry matter produced/kg water used), and its correlation with cultivar isotope discrimination in leaves (Δ) was assessed in peanut plants grown in small canopies in the field. Plants were grown in separate minilysimeters that were both embedded in the ground and positioned above the crop. Differences among cultivars were found in W and � and the relationship between W and Δ was compared for plants grown in open and closed canopies. Genetic variability in W in plants grown in the field under non-limiting water conditions was demonstrated, with Tifton-8, of Virginia habit, having the highest W (3.71 g/kg) and Rangkasbitung, an Indonesian cultivar of Spanish habit, the lowest (2.46 g/ kg). Variability in W was due to variation in total dry matter production more than that of water use. A strong negative correlation was found between Δ and W, and also between Δ and total dry matter. The relationship between whole plant W, including roots, and Δ was stronger than that between shoot W, without roots and Δ. The improvement occurred because of variation among cultivars in the root to shoot ratio. This highlights the importance of taking account of root dry matter in studies concerning W. There were significant differences in W and Δ between plants in pots above-ground compared to pots in the ground, with above-ground plants having significantly lower values of both W and Δ. The ranking of W and Δ among cultivars was not affected by the contrast in environment, which suggests these parameters are under strong genetic control. Total above-ground dry matter yield at maturity was negatively correlated with Δ, while pod yield was not. It appears a negative association between harvest index and Δ may exist; however not all cultivars used in this and other studies follow this response. Both water-use efficiency, Wand total dry matter production are negatively correlated with Δ in leaves of peanut plants grown in small canopies in the field. Measurement of Δ may prove a useful trait for selecting cultivars with improved W and total dry matter yield under field conditions.


2020 ◽  
Vol 22 (1) ◽  
pp. 47-56
Author(s):  
Faruque Ahmed ◽  
IM Ahmed ◽  
N Mokarroma ◽  
F Begum ◽  
A Jahan

A pot experiment was conducted with five selected rapeseed/mustard genotypes (BJDH-11, BJDH-12, BJDH-20, BARI Sarisha-14, and BARI Sarisha-16) under two sowing dates (November 20 and December 20) for evaluating their responses to sowing date induced high temperature stress during rabi season of 2017-18. Sowing dates induced temperature variability showed remarkable changes in pheonlogy, leaf area, leaf chlorophyll content, dry matter production and seed yield. Although December 20 sown crop received lower temperatures (minimum 9.8 to 13.2 and maximum 22.6 to 27oC) than November 20 sown crop (minimum 14.8 to 16.4 and maximum 21 to 27.2oC) at flowering but reverse was found at grain development stage. Grain development stage of November 20sown crop received lower temperatures (minimum 8.2 to 13.2 and maximum 24.1 to 27 oC) while December 20 sown crop received higher temperatures at grain development stage (minimum 8.2 to 18 and maximum 22.6 to 32.5oC).As a result December 20 sown crop matured earlier (6 to 9 days) than November 20 sown crop. Leaf area/plant was higher in December 20 sown crops compared to November 20 sown but total dry matter production was more or less same in both the sowing dates. Leaf chlorophyll content did not show any remarkable variation due to variation in sowing dates. However, antioxidant activity like Catalyse (CAT), Peroxidase (POD) Ascorbate peroxidase (APX) and Malondial dehyde (MDA) were found higher in December 20 sown crops than that of November 20sown. Higher activity of APX, POD and CAT with lower activity of MDA indicates comparatively high temperature tolerant genotype. Among the genotypes APX, POD and CAT activity were found higher with lower activity of MDA in BJDH-11 and BJDH-20 and these genotypes also gave higher yield than others. On the basis of growth parameters, antioxidant activity and seed yield of genotype BJDH-11 and BJDH-20 could be select as terminal high temperature tolerance genotypes. Bangladesh Agron. J. 2019, 22(1): 47-56


2012 ◽  
Vol 60 (3) ◽  
pp. 191-200 ◽  
Author(s):  
A. Anda

The effect of spraying maize weekly with a 0.5 M concentration of Cd was studied in Hungary at two water supply levels. Cd reduced the size of the leaf area and the annual water loss. The intensity of evapotranspiration (mm water/unit leaf area) of the polluted crops grew. The higher net radiation of polluted maize resulted in an increase in sensible heat and a warmer canopy. The warmer the canopy, the higher the stress level of the contaminated crops was. While Cd caused a 28% significant decline in plant dry matter production in the rainfed plots, only a declining tendency amounting to a few percent was recorded in the ET treatment.Cd of atmospheric origin was only detected in the leaves; it was not accumulated in the grain. It was concluded from the results that the yield losses in grain maize grown on Cd-polluted areas could be mitigated by irrigation. The production of silage maize, however, is not recommended in regions affected by Cd pollution, especially in areas where irrigation is required, since supplementary water supplies promote the accumulation of Cd in the vegetative organs.


1969 ◽  
Vol 49 (3) ◽  
pp. 339-349 ◽  
Author(s):  
H. Gasser ◽  
L. Lachance ◽  
P. Gervais

In two experiments, one with alfalfa and the other with birdsfoot trefoil, we have been able to show that a late cut in October does not adversely affect dry matter yield (DAI) of the legumes. Three cuts during a harvesting season ending on September 5 were detrimental to alfalfa, since lower yields were obtained the following year of harvest. Birdsfoot trefoil varieties were affected differentially. Three cuts did not affect the yield of Viking the following year, but did so of Empire. Significant differences in dry matter yields were obtained between DuPuits and Vernal and between Viking and Empire. Protein in the forage followed inversely the same pattern as that of DM yields, that is, where the intervals were shortest, the protein content was highest, and conversely. The total available carbohydrate and the nitrogen content of the roots were lowest following the treatments which had the shortest intervals between them.


Crop Science ◽  
2002 ◽  
Vol 42 (1) ◽  
pp. 146-151 ◽  
Author(s):  
P. Q. Craufurd ◽  
P. V. Vara Prasad ◽  
R. J. Summerfield

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