Effect of superphosphate application on macro-nutrient and micro-nutrient concentrations in grazed stylo-native grass pasture in tropical Australia

1992 ◽  
Vol 43 (8) ◽  
pp. 1725
Author(s):  
RE Hendricksen ◽  
MA Gilbert ◽  
LD Punter

Soils of northern Australia are generally old, strongly weathered, and of low fertility status. Some knowledge of the status of nitrogen, phosphorus and sulfur and its effects on pasture productivity is available from small plot trials, but few detailed studies of macro-nutrient and micro-nutrient levels in grazed pastures have been reported. Such a study from a site near Mareeba in north Queensland has recently been completed. The major components of the pasture were kangaroo grass ( Themeda triandra), giant speargrass (Heteropogon triticeus) and the legumes, Stylosanthes scabra cv. Seca and S. hamata cv. Verano, which were oversown into the native grass pasture 6 years previously. Generally, the effects of superphosphate on nutrient concentration were minor compared with the effects of season, plant part and species. Superphosphate application increased concentrations of P and S, but decreased concentrations of Zn and Mo and the N/S ratio in both sets of legume and grass. There was no effect on the concentrations of N, K, Na, Ca, Cu and Co. Fertilizer effects did not often interact significantly (P < 0.05) with season, species and plant part (green leaf and stem). Seasonal changes in nutrient concentration were not consistent for all nutrients. As the growing season progressed from December to June, concentrations of the mobile nutrients, N, P, K, Na, Cl, S, Se and I decreased, the immobile nutrients Ca and Mo increased, but Mg, Cu and Co and the N/S ratio remained relatively constant. Both Zn and Mn concentrations remained constant with season in the legumes, but increased in the grasses. Season * species interactions were often significant for the grasses possibly due to the differing maturity patterns of kangaroo grass and giant spear grass. Cattle grazing the native pasture during the wet season are likely to be deficient in N, P, Na, S and Cu based on the nutrient concentrations in plucked pasture samples and published dietary requirements. However, cattle grazing productive stylo - native grass pasture which has received adequate single superphosphate are likely to suffer only from Na deficiency. At suboptimal levels of superphosphate, a deficiency of P in the diet is also indicated.

2019 ◽  
Vol 70 (12) ◽  
pp. 1044
Author(s):  
M. L. Mitchell ◽  
M. R. McCaskill ◽  
R. D. Armstrong

Approximately 3.1 Mha (22%) of the agricultural area of south-eastern Australia can be classified as native pasture. There is the assumption that, owing to the widespread occurrence of low-fertility soils in Australia, native grass species do not respond to increased phosphorus (P) fertility. Currently, there are no industry recommendations of target soil-test P values for native-grass-based pastures. This paper reviews the responses of perennial native pasture species endemic to south-eastern Australia to P application in controlled environments, surveys, replicated experiments and paired-paddock trials. Eighty-seven site-years of trial data where different levels of P were applied, conducted over the last two decades, on native-based pastures in south-eastern Australia are reviewed. Data indicate that application of P fertilisers to native grass pastures can increase dry matter (DM) production and maintain pasture stability. However, minimum targets for herbage mass (800 kg DM/ha) and groundcover (80%) are required to ensure persistence of perennial native grasses. Stocking rates also need to match carrying capacity of the pasture. Based on previous research, we recommend target soil-test (Olsen; 0–10 cm) P levels for fertility-tolerant native grass pastures, based on Microlaena stipoides, Rytidosperma caespitosum, R. fulvum, R. richardsonii, R. duttonianum and R. racemosum, of 10–13 mg/kg, whereas for pastures based on fertility-intolerant species such as Themeda triandra, lower levels of &lt;6 mg/kg are required to ensure botanical stability.


2015 ◽  
Vol 87 (2) ◽  
pp. 813-823 ◽  
Author(s):  
Marcelo C. de Souza ◽  
Paula C.P. Bueno ◽  
Leonor P.C. Morellato ◽  
Gustavo Habermann

The cerrado's flora comprises aluminum-(Al) accumulating and non-accumulating plants, which coexist on acidic and Al-rich soils with low fertility. Despite their existence, the ecological importance or biological strategies of these functional groups have been little explored. We evaluated the leaf flushing patterns of both groups throughout a year; leaf concentrations of N, P, K, Ca, Mg, S, Al, total flavonoids and polyphenols; as well as the specific leaf area (SLA) on young and mature leaves within and between the groups. In Al-accumulating plants, leaf flushed throughout the year, mainly in May and September; for non-accumulating plants, leaf flushing peaked at the dry-wet seasons transition. However, these behaviors could not be associated with strategies for building up concentrations of defense compounds in leaves of any functional groups. Al-accumulating plants showed low leaf nutrient concentrations, while non-accumulating plants accumulated more macronutrients and produced leaves with high SLA since the juvenile leaf phase. This demonstrates that the increase in SLA is slower in Al-accumulating plants that are likely to achieve SLA values comparable to the rest of the plant community only in the wet season, when sunlight capture is important for the growth of new branches.


1989 ◽  
Vol 29 (5) ◽  
pp. 613 ◽  
Author(s):  
WH Winter ◽  
JJ Mott ◽  
RW McLean ◽  
D Ratcliff

Options for increasing pasture and animal production from native perennial pastures comprising predominantly Themeda triandra, Chrysopogon fallax, Sehima nervosum and Sorghum plumosum were studied over 5 years at Katherine in the semi-arid tropics of north-western Australia. The pastures were augmented with either Stylosanthes humilis, S. hamata or a mixture of S. scabra and S. viscosa, either without fertiliser or with low inputs of superphosphate (100 kg/ha at establishment and 25 kg/ha annually), and with the trees either killed or left undisturbed. At each fertiliser level there were 3 stocking rates. Five years after sowing, only half of the pastures persisted, due to the poor productivity of the legumes and the inability of the native perennial grasses to tolerate high grazing pressure which was about 10-fold that for non-augmented native pasture. This effect was greater in the unfertilised treatments, where the legume contributed less to pasture yield, so that the sustainable stocking rate was only half of that for pastures fertilised with small amounts of superphosphate. When fertilised, stable pastures of nearly pure legume were obtained after 3-4 years at the highest stocking rate of 1 steer/ha. Fertiliser also (i) increased the nitrogen and sulfur concentrations of S. humilis and the perennial stylos S. scabra and S. viscosa, but lowered their concentrations in S. hamata, particularly in the early wet season; (ii) decreased nitrogen concentration in Chrysopogon fallax; and (iii) increased phosphorus and sulfur concentrations of all the perennial grasses. In general, fertiliser promoted higher liveweight gains of cattle during the wet season and lower losses during the dry season. In the fertilised treatments growth tended to be poorer at the highest stocking rate, particularly during the late dry and early wet seasons. This effect was attributed to spoilage of dry legume by the early rainfall and lack of grass in these treatments. We conclude that S. hamata, S. scabra and S. viscosa grow reasonably well in soils of low fertility, but the productivity of the legumes and of the cattle can be improved by small inputs of superphosphate. The mediocre growth of the cattle in all the treatments may have been due to the low levels of some nutrients, particularly phosphorus and sulfur, in these pastures.


2012 ◽  
Vol 63 (9) ◽  
pp. 788 ◽  
Author(s):  
N. E. Pettit ◽  
T. D. Jardine ◽  
S. K. Hamilton ◽  
V. Sinnamon ◽  
D. Valdez ◽  
...  

The present study indicates the critical role of hydrologic connectivity in floodplain waterholes in the wet–dry tropics of northern Australia. These waterbodies provide dry-season refugia for plants and animals, are a hotspot of productivity, and are a critical part in the subsistence economy of many remote Aboriginal communities. We examined seasonal changes in water quality and aquatic plant cover of floodplain waterholes, and related changes to variation of waterhole depth and visitation by livestock. The waterholes showed declining water quality through the dry season, which was exacerbated by more frequent cattle usage as conditions became progressively drier, which also increased turbidity and nutrient concentrations. Aquatic macrophyte biomass was highest in the early dry season, and declined as the dry season progressed. Remaining macrophytes were flushed out by the first wet-season flows, although they quickly re-establish later during the wet season. Waterholes of greater depth were more resistant to the effects of cattle disturbance, and seasonal flushing of the waterholes with wet-season flooding homogenised the water quality and increased plant cover of previously disparate waterholes. Therefore, maintaining high levels of connectivity between the river and its floodplain is vital for the persistence of these waterholes.


1992 ◽  
Vol 43 (2) ◽  
pp. 241 ◽  
Author(s):  
JJ Mott ◽  
MM Ludlow ◽  
JH Richards ◽  
AD Parsons

The close correlation between grazing-induced mortality and major climatic patterns in Australian savannas, led us to the hypothesis that moisture conditions during the dry, non-growing season could affect sensitivity to grazing in the subsequent growing season. Using three widespread savanna species (Themeda triandra, Heteropogon contortus and Panicum maximum), this hypothesis was tested experimentally and the mechanisms controlling this response examined and quantified. In T. triandra drought during the dry season led to major mortality in defoliated plants in the next growing season. This mortality was caused by a synchrony of tillering at the commencement of the wet season, leaving few buds for replacement once parent tillers were killed by defoliation. T. triandra was also the most sensitive species to defoliation. This sensitivity was due to the poor ability of the plant to maintain positive carbon gain after defoliation. Several factors contributed to this poor ability, including: low total photosynthetic rate, low specific leaf area, and a large proportion of sheath material with poor photosynthetic capacity remaining after cutting. Both H. contortus and P. maximum growing under irrigated and fertilized conditions did not display any effects of previous moisture treatments when defoliated during the next wet season and were much less sensitive to defoliation than T. triandra.


1969 ◽  
Vol 65 (2) ◽  
pp. 123-128
Author(s):  
J. C. W. Keng ◽  
T. W. Scott ◽  
M. A. Lugo-López

A drip irrigation system using porous plastic tubing was designed to study operational techniques of drip irrigation and fertilizer management in a highly weathered, leached, relatively low fertility, acid Oxisol. Sweet pepper (Capsicum annuum) was the test crop. All plots received an initial broadcast application of a 10-4.4-8.3 N-P-K fertilizer at the rate of 80 kg/ha. The experiment followed a randomized complete block layout with 4 treatments and 6 replications. The treatments were as follows: 1) N and K injected into the drip system, P banded; 2) banded N, P and K with drip irrigation; 3) broadcast N, P and K with drip irrigation; and 4) control-drip irrigation, no N, P and K other than the initial overall broadcast application. All treatments, except the control, received a total of 56.8 g of a 10-10-10 fertilizer per plant and all were uniformly drip irrigated according to pan evaporation data. Two crops were grown: one in the dry season and one in wet season. Yields were significantly different among all treatments for the dry season crop, with a high of 82.62 kg/ha for the treatments where Nand K were injected into the drip system and a low of 31.54 kg/ha for the control. For the wet season crop, no significant yield differences were found when fertilizer was injected into the drip system and when banded, but both these treatments were superior in yield to that of broadcast. These three treatments were superior to the control, with more than 100% increase. Drip irrigation is a promising alternative to currently used water-nutrient management methods for Oxisols in the wet-dry tropics.


2006 ◽  
Vol 34 ◽  
pp. 35-40
Author(s):  
Hanne H. Hansen ◽  
Jørgen Madsen

SummaryThe diet of cattle grazing in the Sanyati communal area, Zimbabwe was determined using plant particle identification from faeces from intact animals, and faeces and oesophageal extrusa from fistulated animals. A total of 130 plant genus, species and types were identified. The twenty most frequently occurring species in the samples comprised between 76 and 90% of the identifiable diet. The most frequent grass species were more than half of the identified diet in the dry season while they were half or less of the identified diet in the wet season. There were more plant species identified in the wet season than in the dry season. Significant differences were found when comparing the plant species identified in faeces to those in oesophageal extrusa from fistulated animals. This may be due to incomplete recovery of ingesta in the bags, or to the loss of identifiable particles in the faeces when compared to oesophageal extrusa because of digestibility. More research is needed to validate the use of oesophageal extrusa for diet botanical determination.


HortScience ◽  
2017 ◽  
Vol 52 (12) ◽  
pp. 1707-1715 ◽  
Author(s):  
Salvatore Campisi-Pinto ◽  
Yusheng Zheng ◽  
Philippe E. Rolshausen ◽  
David E. Crowley ◽  
Ben Faber ◽  
...  

Optimizing ‘Hass’ avocado (Persea americana Mill.) tree nutrient status is essential for maximizing productivity. Leaf nutrient analysis is used to guide avocado fertilization to maintain tree nutrition. The goal of this research was to identify a ‘Hass’ avocado tissue with nutrient concentrations predictive of yields greater than 40 kg of fruit per tree. This threshold was specified to assist the California avocado industry to increase yields to ≈11,200 kg·ha−1. Nutrient concentrations of cauliflower stage inflorescences (CSI) collected in March proved better predictors of yield than inflorescences collected at full bloom (FBI) in April, fruit pedicels (FP) collected at five different stages of avocado tree phenology from the end of fruit set in June through April the following spring when mature fruit enter a second period of exponential growth, or 6-month-old spring flush leaves (LF) from nonbearing vegetative shoots collected in September (California avocado industry standard). For CSI tissue, concentrations of seven nutrients, nitrogen (N), phosphorus (P), potassium (K), magnesium (Mg), sulfur (S), zinc (Zn), and copper (Cu) were predictive of trees producing greater than 40 kg of fruit annually. Conditional quantile sampling and frequency analysis were used to identify optimum nutrient concentration ranges (ONCR) for each nutrient. Optimum ratios between nutrient concentrations and yields greater than 40 kg per tree were also derived. The high nutrient concentrations characterizing CSI tissue suggest current fertilization practices (timing or amounts) might be causing nutrient imbalances at this stage of avocado tree phenology that are limiting productivity, a possibility that warrants further investigation. Because CSI samples can be collected 4–6 weeks before full bloom, nutritional problems can be addressed before they affect flower retention and fruit set to increase current crop yield, fruit size, and quality. Thus, CSI nutrient analysis warrants further research as a potential supplemental or alternative tool for diagnosing ‘Hass’ avocado tree nutrient status and increasing yield.


HortScience ◽  
2017 ◽  
Vol 52 (12) ◽  
pp. 1728-1733 ◽  
Author(s):  
Martin M. Maboko ◽  
Christian Phillipus Du Plooy ◽  
Silence Chiloane

Nutrient application is one of the major inputs required for hydroponic production of cucumbers. Reduced nutrient solution concentration with supplementary foliar fertilizer application may maintain yield and quality of mini-cucumber, while decreasing the production costs. An experiment was conducted to determine the effect of foliar fertilizer in combination with reduced nutrient concentrations on the yield and quality of hydroponically grown mini-cucumber in a plastic tunnel. Mini-cucumber plants were grown in sawdust, fertigated with nutrient solutions containing 100% (control), 75%, 50%, or 25% of the recommended nutrient concentration (NC) and two foliar fertilizer applications (no foliar and foliar application). The highest fresh and dry weight of mini-cucumber plants were obtained with 75% and 100% NC and decreased with 50% to 25% NC application. The number of marketable fruit and marketable yield on mini-cucumbers increased with 75% to 100% NC, followed by 50% NC, as compared with 25% NC. Deformed fruit were significantly lower at 25% NC than at 50%, 75%, and 100% NC. Foliar fertilizer application did not have an effect on mini-cucumber yield, but reduced the yellowing of fruit. Fruit mineral content (P, Fe, and Mn) was significantly improved by 100% NC. Improvement in yield at 75% and 100% NC was as a result of improved plant height, leaf chlorophyll content, plant fresh and dry weight, and the increase in nutrient uptake of N, P, K, and Mn, which was evident in the analysis of cucumber leaves. The reduced NC of 75% can maintain yield and quality of mini-cucumbers, whereas the application of foliar fertilizer had a limited effect.


1974 ◽  
Vol 14 (66) ◽  
pp. 112 ◽  
Author(s):  
DW Turner ◽  
B Barkus

At Alstonville, New South Wales, leaf position had a greater effect than season on the nutrient concentrations of N, P, K, Ca, Mn, Cu, and Zn in the laminae of Williams bananas growing on a krasnozem soil and sampled over a 4-year period. However, season was more important for Mg. The effect of stage of plant growth was significant but much smaller than the other influences. When sampling for leaf analysis, leaf position and plant age can be standardised, but a major problem in this investigation was unpredictable, significant changes in nutrient composition from one sampling date to another. If these results are true for other soils. the data do not allow critical levels to be applied.


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