Agricultural Science Commons^™

Improvement Strategies In Winter Cold Temperate Rangeland Ecosystems With Particular Reference To Extensive Grazing Lands Of Iran, A Koocheki

IGC Proceedings (1977-2023)

Traditional land use systems in Iran have been divided between crop production and livestock grazing. Grazing land management in most parts is based on pastoral nomadism which operates between plains as winter grazing lands and mountains as summer grazing lands. Mountainous areas are an important source of food and feed production for nomads and their herds. In Iran two main ranges of mountains, Elburz and Zagros, are the summer territory of nomadic pastoralists. At present 1.5% of total population of the country are nomads. They contribute as much as 27% of value added in the animal industry of the country. …

Winter Cold Temperate Rangelands: Improvement Strategies For Intensive Rangeland Ecosystems, B E. Allan, D Scott

IGC Proceedings (1977-2023)

Transfer of developed grassland technologies to rangelands is discussed in terms of environmental gradients and the options and constraints they impose. Winier feed limitation can be overcome through conserved feeds and various in situ systems involving special purpose pastures and feed banks. General animal nutrition can be improved through intensive development, low input systems, better control of range utilisation and, where appropriate, correction of mineral deficiencies. The emphasis in seeking quick and easy solutions to rangeland management problems is questioned, A more informed, environmentally sound and sustainable approach to rangeland fanning atlitudes and management is proposed. A stepwise process to …

Evaporation Basins For Salinity Management, Department Of Primary Industries And Regional Development, Western Australia

Natural resources factsheets

An evaporation basin is an engineered earth structure designed to safely store and evaporate saline water discharged from drainage or pumping, while protecting high-value agricultural land, natural assets or built infrastructure.

DPIRD recommends that evaporation basins should form part of an integrated water and salinity management program. Information on this page is a guide only.

It is recommended that landholders seek expert advice plus engineering design and related support from qualified contractors.

Measuring Soil Salinity, Department Of Primary Industries And Regional Development, Western Australia

Natural resources factsheets

To make sound decisions on managing saline sites, you need to know the source of salt, how salinisation is occurring, the landscape context, and most importantly, the actual salt concentration of the soil.

The most common 'measures' of salt concentration are actually estimates based on electrical conductivity of a soil and water solution. Soil salt content can be measured in a laboratory by measuring the total dissolved solids in a sample. In the field, salt concentration can also be estimated using electromagnetic induction-based soil sensors.

Excavated Tanks (Farm Dams), Department Of Primary Industries And Regional Development, Western Australia

Natural resources factsheets

Guidelines and information for planning, legal requirements, design, construction and management of excavated tanks for water storage on farm.

Excavated tanks (farm dams) provide effective water storage wherever surface water run-off can be harvested for livestock, crop spraying, irrigation and domestic use on rural properties.

Excavated tanks for rainfall storage are common in the southern agricultural areas of WA.

Well-designed and constructed dams are farm assets, safe and require little maintenance.

Poor design and construction can lead to poor water harvesting and storage, excessive costs, downstream erosion and risks to property and people.

DPIRD recommends that excavated tanks should be …

Pumping Groundwater For Salinity Control In Wa, Department Of Primary Industries And Regional Development, Western Australia

Natural resources factsheets

DPIRD recommends that groundwater pumping is used as part of an integrated water and salinity management program.

Groundwater pumping can lower local water tables, recover land for production and reduce the spread of local salinity or to protect high value assets at risk, such as townsites, roads or railway lines. Pump water can be discharged to safe disposal points or used on farm for desalination.

Roaded Catchments In Wa, Department Of Primary Industries And Regional Development, Western Australia

Natural resources factsheets

Roaded catchments are earthwork structures designed to increase the amount of run-off from the catchment above a receiving farm dam.

Roaded catchments are lined with clay and compacted to make a smooth surface that reduces infiltration and increases run-off. Roaded catchments should discharge into a silt trap and then into a dam (excavated earth tank). This combined structure should be fenced to exclude livestock.

The Department of Primary Industries and Regional Development recommends that roaded catchments are part of an integrated water and salinity management program.

The information in this page is only a guide – seek expert advice before …

Managing Subsurface Water In Wa, Department Of Primary Industries And Regional Development, Western Australia

Natural resources factsheets

The Department of Primary Industries and Regional Development (DPIRD) recommends that subsurface water management is part of an integrated water and salinity program. An integrated program can help to lower water tables and alleviate problems with waterlogging, rising salinity, and infrastructure damage.

Rabbit Fencing To Protect Crops And Pastures, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity factsheets

This factsheet outlines the use of fencing to protect crops and pasture from rabbits.

Rabbits cause an estimated loss of $217 million each year to Australian agricultural production and cause significant environmental damage. In Western Australia (WA), areas of native vegetation, particularly on sandy ridges that would otherwise be subject to wind erosion, have been retained on farms. Bush remnants are a major refuge habitat for rabbits, which can cause considerable damage to nearby pastures and crops. A measure of rabbit control can be achieved by poisoning around bush remnants in late summer or autumn, prior to seeding. To be …

Evaluation Of Dual Purpose Canola And Cereals Grazed With Cattle, Department Of Primary Industries And Regional Development, Western Australia

Animal production and livestock factsheets

The Department of Primary Industries and Regional Development conducted research to investigate and demonstrate the importance of dual-purpose crops (canola, wheat and barley) to improve the feed availability for cattle (in late autumn to early winter) in mixed farming systems of the high rainfall environment of Western Australia (WA).

The grain yield of a wide range of canola and cereal varieties sown in mid-April were unaffected by the grazing of cattle at a stocking rate of 20 to 22 dry sheep equivalent (DSE) per hectare (ha) for up to 4 weeks at Esperance in 2011.

The grazed crops yielded the …

Rabbit Control: Warren And Harbourage Destruction, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity factsheets

If correctly and appropriately undertaken, the destruction of rabbit warrens, or modification of the habitat so it becomes less favourable to rabbits, can be an important and effective part of reducing the impacts of rabbits.

Destruction of warrens can improve the overall effectiveness of rabbit control programs, even though many rabbits live and shelter above-ground under bushes, and in scrub). If undertaken properly, the ripping of rabbit warrens can often provide a relatively permanent and long-term benefit. Similarly, removing or modifying other forms of rabbit-harbourage (for example, removing rock piles) can help, particularly in semi-urban areas or on smallholdings.

Argentine Ants, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity factsheets

Argentine ants (Linepithema humile) are small, brown, and notorious worldwide for being one of the most difficult and costly ants to control, as it can involve ongoing and repetitive use of residual, contact insecticides. The ants are established in Western Australia (WA).

Electric Ant (Little Fire Ant), Department Of Primary Industries And Regional Development, Western Australia

Biosecurity factsheets

The electric ant (Wasmannia auropunctata), also known as little fire ant, is a tiny, gold-brown coloured ant, and one of the world's most invasive pests. Electric ants prey on and compete with other insects and can displace large numbers of native animals, ants, and other insects.

They affect human health and lifestyle, can inflict painful stings on humans and wild and domestic animals, can blind pets, damage the environment, and have the potential to severely affect agricultural industries.

The electric ant is native to Central and South America and was first detected in Australia in 2006 in Queensland, where there …

Effect Of Crop Age On Seed Yield Of Arachis Pintoi At Two Sites In Costa Rica, Pedro J. Argel, Alfredo Valerio

IGC Proceedings (1977-2023)

Arachis pintoi is a forage legume well adapted to the humid tropics of Costa Rica. Seed production studies were carried out at two contrasting localities within the country, Gulipiles (very humid tropics) and San Isidro (seasonal evergreen tropical forest). The accessions CIAT 18748, 18744 and 17434 cv. Amarillo of A. pinloi were vegetatively planted at both sites. Seed yields were measured at 8, 12, 16 and 20 months post- planting inGulipiles, and at·8, 16 and 20 months in San Isidro. Mean seed yields among accessions were similar in San Isidro but significantly different in Gulipiles; however, the contrary occurred in …

Efficient Nitrogen Fertilization In Grass Seed Crops With Regard To Soil Mineral Nitrogen Content And Analyzing Grass Tillers In Spring, W Schoberlein, H J. Wahl

IGC Proceedings (1977-2023)

When applying the Nmln method in grass seed crops analogously lo that in cereal crops we proceed from the experience that for a mean level of mineralisation, the sum total of soil-borne Nm1n available to plants at the beginning of the growth period and Nd Input in the form of fertiliser will provide sufficient N to the crop. The total quantity of mineral soil-borne N and fertiliser N is considered as the nominal value. The required N input can be derived from the difference between nominal value and mineral soil-borne N (Nd = nominal value• Nrnin>· For Dactylis glomerata …

Effects Of Aneuploidy On Seed Production In Autopolyploid Forage Crops, A Elgersma

IGC Proceedings (1977-2023)

Between the selection of a population and its commercial use, several generations of multiplication are necessary. The essential feature in variety maintenance is that no genetic changes occur during multiplication. In seed-propagated species, however, during each multiplication cycle natural selection takes place at ihe gamete, zygote, seed and plant level. In induced autopolyploids high frequencies of aneuploids can occur. Aneuploidy not only affects the seed yield level, but also the selection processes that occur during multiplication. It may cause genetic shift and affect variety stability. Species differ in their tolerance to aneuploids. It is not possible to eliminate aneuploidy by …

Effects Of Ratooning And Protection From Diseases And Birds On Seed Production In Guinea Grass, Okoro Oji, F N. Madubuike, F.O C. Ezedinma

IGC Proceedings (1977-2023)

Effects of ratooning and protection from diseases and birds on seed production in guinea grass (Pannicum maximum L.) were assessed in a study from October 1986 to April 1987. Treatments included ratooning and mancozeb application with or without protection from birds (netting). Highest yield occurred with combined netting and mancozeb application. Mancozeb sp,aying without netting gave lower seed yield than netting without fungicide spraying. Seed yield, which generally decreased with ratooning, was lowest among unnetted and unsprayed crops. Prom anthesis to seed maturation lasted, on average, 9 days, and seeds borne on the upper part of the panicle matured …

Potential For Improved Honey Bee Pollination Efficiency From Easy-To-Trip Lucerne, L R. Teuber, E E. Knapp

IGC Proceedings (1977-2023)

The principal pollinator of lucerne (Medicago sativa L.) in California, USA is the honey bee (Apis mellifera L.). However, honey bees are notoriously inefficient pollinators of lucerne because they learn to avoid tripping the floret. Easy-to-trip lucerne florets could reduce this problem. These studies were designed to determine the inheritance of ease of tripping and assess the effect of ease of tripping on the rate of outcrossing. Both additive and digenic variance for ease of tripping were significant, resulting in a heritability of 34.0:1:16.2%. Ease of tripping had no influence on outcrossing rate, which was estimated to average …

Effect Of Final Cutting For Fodder On Seed Yield And Seed Quality In Berseem, S L. Saini, R K. Chowdhury

IGC Proceedings (1977-2023)

The study was conducted to determine the appropriate time of final culling (closing) for fodder to optimise the seed yield and seed quality in berseem (Trifolium alexandrinum L.). Based on 2 years' experimentation, the maximum seed yield was obtained when the final cut for fodder was taken in mid•March and the crop was then closed for seed. Seed yield was reduced drastically when the final cut was delayed to late March•April. The seed quality parameters of standard germination, seed weight and vigour index were also reduced when the final cut for fodder was delayed to late March•early April. Based …

Effect Of Post-Harvest Management Practices On Seed Yields On Fine-Leaf Fescue, Gale A. Gingrich, William C. Young Iii, Thomas B. Silberstein

IGC Proceedings (1977-2023)

Public opposition and legislative actions have restricted the practice of open-field burning of grass seed fields in Western Oregon's Willamette Valley. Finding economically acceptable alternatives to straw residue removal has become a priority for valley grass seed growers. Trials using 4 residue management practices were established on 2 commercial fine fescue (Festuca rubra) seed fields. Seed yields varied significantly between residue management practices. Seed yields from thermal-treated plots were equal or significantly greater than yields from the non-thermal treatments. Fertile tiller number was also greater with thermal treatments. Most fine fescue fields produce 4-6 seed crops before replanting, …

Floret Site Utilization Of White Clover, A H. Marshall, D H. Hides

IGC Proceedings (1977-2023)

Plants of white clover (Trifolium repensL.) cv. Olwen were grown in an open glasshouse at 20°C and ovule growth and development measured. Differences in the rate of growth of ovules within ovaries were observed as early as 2 days after pollination. Ovules reached a maximum size after 8 days, with the smallest only half the size of the largest. After 8 days the smallest ovules became flaccid and shrivelled. Ovule position within the ovary had no effect on the frequency of seed set. Inflorescence position and floret position on the inflorescence had a significant effect on the number …

Influence Of Harvest Date On The Yield And Quality Of Seed Of Phalaris, K Reddy, W R. Scott, R J. Lucas

IGC Proceedings (1977-2023)

Grasslands Maru phalaris (Phalaris aquatica L,) was harvested every third day commencing 12 days after mid-anthesis (DAA) to define the optimum time of harvest for seed yield and quality. Harvesting earlier than 21-24 DAA reduced 1000-seed weight and viability. Delaying harvest until 24 days reduced seed yield due to shattering but had no detrimental effect on seed weight and viability. Heavy seed losses occurred 24 DAA when seed moisture fell below 40%. The results of this experiment suggest that Maru phalaris should be harvested 21-24 DAA when the seed moisture is in the range of 40-42% to reduce the …

Annual Bluegrass And Rat's Tail Fescue Control In Perennial Ryegrass, M E. Mellbye, William C. Young Iii, George W. Mueller-Warrant

IGC Proceedings (1977-2023)

Annual bh1egrass (Poa annua L.) and rat's-tail fescue (Vulpia myruros (L.) C.C. Omel.) are common weed contaminants in seed from perennial ryegrass fields Lolium perenne L. grown in Oregon. A trial was conducted to evaluate post-harvest residue removal methods and herbicides to reduce the level of these impurities. The best weed control was obtained from herbicides following crew-cut management, a comparatively thorough non-thermal nppronch to residue removal. Control was good with sequential herbicide treatments, especially when an effective pre-emergence herbicide such as pendimethalin was used, although no treatment completely eliminated annual bluegrass and rat's-tail fescue from threshed seed samples …

Flowering And Seed Production Of Centrosema Spp. In Relation To Day Length And Temperature, R.J M. Gonzalez, R J. Clements, L R. Humphreys

IGC Proceedings (1977-2023)

The effcc1s of variation in daylength and temperature on the flowering processes leading to seed production were studied in genotypes of 5 Centrosema spp. Short days (11 h) enhanced flowering in accessions of C. virginatum from low latitude but flowering of lines from high latitude was more prolific in 16-h days. A quantitative long-short day response was evident in 2 intermediate latitude accessions. The critical photoperiod for flowering·varied: C. virginianum cross 31 flowered in 13.5 h or less, C. pubescens, C. pascuorum and C. macrocarpum in 12 h or less, and C. schiediam Oowcred only in a 10.5 …

Herbicide Treatments For Non-Thermal Grass-Seed Production, George W. Mueller-Warrant, William C. Young Iii

IGC Proceedings (1977-2023)

Legislation phasing down open-field burning in the Willamette Valley of Oregon is forcing grass seed growers to alter crop production piactices. Adoption of new mechanical means for straw removal has increased reliance on herbicides. Volunteer seedling control and crop tolerance for 15 herbicide treatment sequences were evaluated in established tall fcscue (Festuca arundinacea) and perennial ryegrass (Lolimn perenne) stands during 2 growing seasons using 5 methods of residue removal. Pre-emergence pendimethalin was extremely safe yet fairly effective on volunteer seedlings in both crops. For perennial ryegrass subsequently treated with post-emergence herbicides, pre-emergence metolachlor was slightly more …

A Development Scale For Perennial Ryegrass, Miriam L. Martin, Roger J. Field

IGC Proceedings (1977-2023)

Vernalised plants of perennial ryeg ra ss (Lolium prenne L. cv. Orasslonds Nui) were grown under controlled conditions and apical development followed by regular excision of apices, which were examined by light and scanning electron microscopy. A 12-point scale describing apical development from the vegetative stage to ear emergence has been produced that is presented in 2 forms: a developmental sequence describing organogenesis events at specific stages, and a commentary on easily recognised features of each stage. The developmental scale provides a detailed analysis that is of value as a botanical description and as a practical aid to those involved …

Seed Yield Potential Of White Clover: Characteristics, Components And Compromise, P.T P. Clifford, I J. Baird

IGC Proceedings (1977-2023)

Nd relationship between leaf size and any of the measured variables was found for 63 agronomically superior white clover (Trifolium repens L.) plants of relatively diverse morphological and physiological characteristics, Predominantly crown-flowering plants gave more than double the seed yield of stolon-lip 'flowerers. High seed yields were also associated with delays in peak flowering, harvest date and increased harvest dry matter. Similar associations were evident for inflorescence density. Increased dry matter accumulation was associated with increases in both floret numbers and seeds/ inflorescence.

Studies In Germination And Thousand-Seed Weight In Chicory Cv. Grasslands Puna, W J. Archie, J S. Rowarth, B R. Guy

IGC Proceedings (1977-2023)

A strong, positive correlation was found between 1000-seed weight (TSW) and germination in chicory (Cichorium intybus L.) cv. Grasslands Puna. Low TSW tended to be associated with empty or immature seed; empty seed was associated with exclusion of bees. No significant differences in seed characteristics were found between seeds harvested from different positions (top, middle or bottom third) on the plant. Optimum harvest lime was 4 weeks after peak flowering.

Seed Production Of Plantain (Plantago Lanceolata L.), J S. Rowarth, M P. Rolston, W J. Archie

IGC Proceedings (1977-2023)

Seed development studies showed that seed maturity in plantain (Plantago lanceolata L,) occurred 6 weeks after anthesis; maximum seed yields were obtained 8 weeks after anthesis. This is consistent with the fact that seed heads take approximately 17 days to complete flowering. Fertiliser nitrogen increased plantain seed yield. Time of closing, timing of nitrogen application and different stand densities did not significantly affect seed yield, probably because plantain can adapt to and compensate for the treatments imposed.

Reproductive Initiation, Closing Dates, Nitrogen Requirements And Harvesting Of Smooth Brome Cv. Grasslands Tiki, J S. Rowarth, W J. Archie

IGC Proceedings (1977-2023)

Reproductive initiation, closing dates, nitrogen requirements and optimum harvest time were investigated for seed production of Grasslands Tiki smooth brome (Bromus inermis Leyss.) in the South Island of New Zealand. Reproductive initiation began in late June, spikelet initiation in mid-September and ear-emergence in mid­October. Seed yield was not affected detrimentally by mowing to 5 cm in mid-September but decreased 24% by mowing in mid-October. Seed yield tended to increase with increasing amounts of N. However, although the highest seed yields were achieved with 50 kg/ha of N in autumn plus I 00 or 150 kg/ha in spring, they did not …