PERENNIAL GRAINS FOR AFRICA: POSSIBILITY OR PIPEDREAM?

SUMMARYPerennial grain crops have been proposed as a transformative approach to agriculture. Replacing annual staple crops with perennialized growth types of the same crops could provide environmental services, improve labour efficiency and weather resilience, reduce seed costs and produce livestock fodder or fuelwood production. Yet, the technologies and science for agricultural development in Africa have focused almost exclusively on annuals. In this paper, we review the literature to explore what has been potentially overlooked, including missed opportunities as well as the disadvantages associated with perennial grains. The case studies of pigeon pea and sorghum are considered, as an analogue for perennial grain crops in Africa. We find that a substantial number of farmers persist in ‘perennializing’ pigeon pea systems through ratoon management, and that sorghum ratoons are widely practiced in some regions. In contrast, many crop scientists are not interested in perennial traits or ratoon management, citing the potential of perennials to harbour disease, and modest yield potential. Indeed, an overriding prioritization of high grain yield response to fertilizer, and not including accessory products such as fodder or soil fertility, has led to multipurpose, perennial life forms being overlooked. Agronomists are encouraged to consider a wide range of indicators of performance for a sustainable approach to agriculture, one that includes management for diversity in crop growth habits.

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Progress Towards Perennial Grains for Prairies and Plains

Outlook on Agriculture ◽

10.1177/00307270211073153 ◽

2022 ◽

pp. 003072702110731

Author(s):

K.G. Cassman ◽

D.J. Connor

Keyword(s):

Grain Yield ◽

Yield Potential ◽

Current Status ◽

Health Food ◽

Environmentally Sustainable ◽

Natural Systems ◽

Grain Crops ◽

Perennial Grains ◽

Perennial Grain ◽

D Investment

Perennial grain crops have been proposed as environmentally sustainable alternatives to annual grain crop systems that currently dominate the world's major breadbaskets. Proponents emphasize the potential of perennial grains to mimic natural systems and thereby reduce soil erosion, nutrient losses, and degradation of soil quality although need for adequate grain yield is also recognized as a prerequisite for success. Here we assess progress since 2005 (16 y) towards development of perennial grain systems with sufficient productivity to be seen as competent alternatives to annual wheat on the prairies and plains of North America and Australia. Based on reports published in refereed journals, we see little evidence that yield of Intermediate Wheatgrass or perennial wheats have improved to the point they are viable alternatives. Slow progress is attributed to lack of minimum grain yield targets for economic viability, lack of designated target regions where perennial grains are most likely to be competitive against annuals, selection methods that focused on components of yield rather than yield per se (i.e. on an area basis), and relatively small R & D investment compared to resources given to genetic and agronomic improvement of major annual grain crops. Given current status, we conclude that perennial grains will require substantial R & D investment and several decades if they are to achieve sufficient yield potential and yield persistence to become more than a niche crop for upscale health food markets in wealthy countries.

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Relative yield and profit of Australian hybrid compared with open-pollinated canola is largely determined by growing-season rainfall

Crop and Pasture Science ◽

10.1071/cp15248 ◽

2016 ◽

Vol 67 (4) ◽

pp. 323 ◽

Cited By ~ 19

Author(s):

Heping Zhang ◽

Jens D. Berger ◽

Mark Seymour ◽

Rohan Brill ◽

Chris Herrmann ◽

...

Keyword(s):

New Technology ◽

Relative Yield ◽

Herbicide Tolerance ◽

Growing Season ◽

Yield Potential ◽

Yield Response ◽

Gross Margin ◽

Roundup Ready ◽

Wide Range ◽

The Cost

Australian canola growers have new technology options including hybrid and herbicide technologies, which have offered yield and profitability advantages in other canola-growing regions of the world. This study compared the yield and gross margins of hybrid and open-pollinated (OP) canola from different herbicide tolerance groups: triazine-tolerant, Roundup Ready, Clearfield and conventional across a wide range of environments in south-western Australia, and in the National Variety Trial network in southern Australia to investigate the relative advantages of these technologies. There were significant differences in yield responsiveness between hybrid and OP canola, the magnitude of which was determined by the growing-season rainfall/available water to the crop. Hybrid out-yielded OP canola in favourable environments where rainfall was high and the growing season was long. However, in areas of low rainfall where yield potential was low, hybrids showed little yield advantage over OP. In contrast, there were no differences in yield response between the four herbicide tolerance groups across the rainfall zones. The economic analysis showed that the break-even yield for hybrids versus OP canola was 1.25 t/ha for triazine-tolerant canola, 0.7 t/ha for Roundup Ready canola, and 1.7 t/ha for hybrid Clearfield canola. The gross margin analysis suggested that hybrid triazine-tolerant, Clearfield and Roundup Ready canola was more profitable than the OP system in the medium (growing-season rainfall of 265–330 mm) and high (330 mm) rainfall environments, but not profitable in the lower (<265 mm) rainfall area because the cost associated with hybrid seed outweighed the small yield benefit. The sensitivity analysis indicated that ± 10% changes in canola price and seed cost shifted the break-even yield by ± 0.1 t/ha. Our study makes a case for Australian canola breeders to maintain OP canola varieties, rather than shifting their focus entirely to hybrids, to underpin continued productivity and profitability in lower rainfall areas.

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Agronomic studies on the productivity of kenaf (Hibiscus cannabinus L. cv. Guatemala 4) under rainfed and irrigated conditions in the Northern Territory

Australian Journal of Experimental Agriculture ◽

10.1071/ea9900395 ◽

1990 ◽

Vol 30 (3) ◽

pp. 395 ◽

Cited By ~ 7

Author(s):

RC Muchow ◽

JD Sturtz ◽

MF Spillman ◽

GE Routley ◽

S Kaplan ◽

...

Keyword(s):

Field Experiments ◽

Plant Density ◽

Northern Territory ◽

Growth And Yield ◽

Stem Length ◽

Yield Potential ◽

Yield Response ◽

Rainfall Season ◽

Wide Range ◽

Average Rainfall

Field experiments were conducted at Berrimah, Douglas Daly and Katherine in the Northern Territory (NT) during the 1987-88 and 1988-89 wet seasons to obtain yield data for kenaf (Hibiscus cannabinzis L. cv. Guatemala 4) grown under rainfed and irrigated conditions. Under rainfed conditions, maximum stem yield was obtained from sowings early in the wet season. Yield decreased with delay in sowing until the late-December-January period. The maximum rainfed stem yield at Katherine in an above-average rainfall season was 18 400 kg/ha. The maximum yield in a below average rainfall season was 11 700 kg/ha at Katherine, 9200 kg/ha at Douglas Daly and 9400 kg/ha at Berrimah. The applicability to the NT of growth and yield relationships established for irrigated kenaf in the Ord Irrigation Area (OIA) was assessed. The yield potential under irrigated conditions in the NT (21 600 kg/ha at 131 days after sowing) was higher than that reported elsewhere in Australia for the same growth period, but similar to that reported elsewhere for longer growth duration (180-300 days). In the NT, in contrast to the OIA, stem yield showed little or no response to N fertilisation. Stem yield was not related to N uptake, and at high levels of N application, there was marked N accumulation in the stem. Kenaf was able to accumulate up to 110 kg N/ha from the soil reserve where no N was applied. The yield response to plant density varied with the yield level and was similar to that in the OIA. Bark and core yield could be estimated directly from biomass, and indirectly from stem length and plant density, over a wide range of yield levels and cultural conditions. It was concluded that data relating to yield potential and response to N fertilisation cannot be transferred directly from the OIA to the NT.

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Understanding perennial wheat adoption as a transformative technology: evidence from the literature and farmers

Renewable Agriculture and Food Systems ◽

10.1017/s1742170515000150 ◽

2015 ◽

Vol 31 (2) ◽

pp. 101-110 ◽

Cited By ~ 16

Author(s):

Jelili Adebiyi ◽

Laura Schmitt Olabisi ◽

Sieglinde Snapp

Keyword(s):

Environmental Issues ◽

Structured Interview ◽

Review Of The Literature ◽

Grain Crops ◽

No Till ◽

Farmer Adoption ◽

Perennial Wheat ◽

Wide Range ◽

Interview Format ◽

Perennial Grain

AbstractPerennial grain crops are an example of a ‘transformative technology,’ in which the functionality and science of the technology differ in a fundamental manner from conventional grain crops. A review of the literature indicates that the motivation for farmer adoption of transformative technologies is complex and poorly understood. At the same time, many studies have found concern and awareness about environmental issues to be significantly and positively correlated with the adoption of no-till agriculture, organic farming and agroforestry. Building on these insights, we conducted an ex ante study of perennial wheat adoption among 11 farmers from Michigan and Ohio. Perennial wheat is not yet commercially available, so a semi-structured interview format was chosen to allow for in-depth discussions of the crop's potential characteristics and uses. Consistent with the literature on transformative technology adoption, farmers who approached us to learn more about perennial grains described soil and environmental quality as their primary motivations for doing so. Farmers suggested a total of ten different uses for perennial wheat, only one of which was mentioned specifically by interviewers. This diversity of proposed uses implied a wide range of criteria for adoption. A striking result was that the ability of perennial wheat to compete with annual wheat on the basis of yield, a focus of researchers, was brought up by only one of the interviewees, as many farmers proposed perennial wheat as a means of solving a problem for which no other crop provided an adequate solution, often by planting perennial wheat on an under-used or marginal area of the farm. This is suggestive that interacting with farmers could alter priorities in perennial grain improvement, as has occurred in other radically transformative agriculture technologies.

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Modelling yield response of a traditional and a modern barley cultivar to different water and nitrogen levels in two contrasting soil types

Crop and Pasture Science ◽

10.1071/cp10317 ◽

2011 ◽

Vol 62 (4) ◽

pp. 289 ◽

Cited By ~ 4

Author(s):

L. Gabriela Abeledo ◽

Daniel F. Calderini ◽

Gustavo A. Slafer

Keyword(s):

Field Research ◽

Yield Potential ◽

Yield Response ◽

Barley Cultivar ◽

Research Information ◽

Deep Soil ◽

Modern Cultivar ◽

Yield Level ◽

Wide Range ◽

Attainable Yield

The importance of yield improvement at farm conditions is highly dependent on the interaction between genotype and environment. The aim of the present work was to assess the attainable yield of a traditional and a modern malting barley cultivar growing under a wide range of soil nitrogen (N) availabilities and different water scenarios (low, intermediate and high rainfall conditions during the fallow period and throughout the crop cycle) considering a 25-year climate dataset for two sites (a shallow and a deep soil) in the Pampas, Argentina. For that purpose, a barley model was first calibrated and validated and then used to expand field research information to a range of conditions that are not only much wider but also more realistic than experiments on experimental farms. Yield of the modern cultivar was at least equal to (under the lowest yielding conditions) or significantly higher (under most growing conditions) than that of the traditional cultivar. Averaged across all the scenarios, yield was ~20% higher in the modern than in the traditional cultivar. The average attainable yield represented 42% of the yield potential in the shallow and 79% in the deep soil profiles. Yield advantage of the high yielding cultivar was based on using N more efficiently, which not only determined higher attainable yields but also reduced the requirements of soil N to achieve a particular yield level. Farmers would face little risk in adopting higher yielding cultivars in both high and low yielding environments and even in the latter ones N fertilisation could be beneficial in most years.

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Assessment of agro-morphological, physiological and yield traits diversity among tropical rice

PeerJ ◽

10.7717/peerj.11752 ◽

2021 ◽

Vol 9 ◽

pp. e11752

Author(s):

Naqeebullah Kakar ◽

Raju Bheemanahalli ◽

Salah Jumaa ◽

Edilberto Redoña ◽

Marilyn L. Warburton ◽

...

Keyword(s):

Gas Exchange ◽

Short Duration ◽

Harvest Index ◽

Yield Potential ◽

Yield Response ◽

Yield Traits ◽

Southern Us ◽

Wide Range ◽

Rice Genotypes ◽

Selection For

Rice (Oryza sativa L.) is an essential staple food crop, but the per acre average rice yield is less than its substantial potential in many countries. Rice breeders and growers would benefit from a robust genotypes with better morpho-physiological and yield-related traits. Here, seventy-four new rice genotypes were phenotyped over two years for their gas exchange and yield potential-related traits under Mississippi rice-growing conditions. A wide range of variability was observed among genotypes for all measured traits. Detailed phenotyping of rice genotypes revealed two key relationships that function together to contribute to yield potential under the southern US climate. The first one, grain yield, grain number, and spikelet fertility, showed considerable correlation (r = 0.45 to 0.79, p < 0.001) to harvest index. Conversely, days to anthesis had a high and negative correlation with harvest index (r = −0.79, p < 0.001), which suggests that selection for short duration genotypes with efficient partitioning could improve the yields under southern US climatic conditions. Additive response index revealed a higher positive association with yield traits (R2 = 0.59) than physiological (R2 = 0.28) and morphological traits (R2 = 0.21). Compared with the commercial genotype Rex, 21.6% and 47.3% of the rice genotypes had a higher gas exchange and yield response scores. IR08A172, IR07K142 and IR07F287 were ranked as high performers in physiological and yield response indices. Our study highlights that selection for short-duration yield-related traits with efficient sink capacity traits is desirable for future breeding programs.

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A sensitivity analysis of the prediction of the nitrogen fertilizer requirement of cauliflower crops using the HRI WELL_N computer model

The Journal of Agricultural Science ◽

10.1017/s0021859601001174 ◽

2001 ◽

Vol 137 (1) ◽

pp. 55-69 ◽

Cited By ~ 5

Author(s):

C. RAHN ◽

A. MEAD ◽

A. DRAYCOTT ◽

R. LILLYWHITE ◽

T. SALO

Keyword(s):

Sensitivity Analysis ◽

Computer Model ◽

N Fertilizer ◽

Yield Potential ◽

Yield Response ◽

Soil Mineral N ◽

Soil Mineral ◽

Mineral N ◽

Wide Range ◽

Fertilizer Requirement

HRI WELL_N is an easy to use computer model, which has been used by farmers and growers since 1994 to predict crop nitrogen (N) requirements for a wide range of agricultural and horticultural crops.A sensitivity analysis was carried out to investigate the model predictions of the N fertilizer requirement of cauliflower crops, and, at that rate, the yield achieved, yield response to the fertilizer applied, N uptake, NO3-N leaching below 30 and 90 cm and mineral N at harvest. The sensitivity to four input factors – soil mineral N before planting, mineralization rate of soil organic matter, expected yield and duration of growth – was assessed. Values of these were chosen to cover ranges between 40% and 160% of values typical for field crops of cauliflowers grown in East Anglia. The assessments were made for three soils – sand, sandy loam and silt – and three rainfall scenarios – an average year and years with 144% or 56% of average rainfall during the growing season. The sensitivity of each output variable to each of the input factors (and interactions between them) was assessed using a unique ‘sequential' analysis of variance approach developed as part of this research project.The most significant factors affecting N fertilizer requirement across all soil types/rainfall amounts were soil mineral N before planting and expected yield. N requirement increased with increasing yield expectation, and decreased with increasing amounts of soil mineral N before planting. The responses to soil mineral N were much greater when higher yields were expected. Retention of N in the rooting zone was predicted to be poor on light soils in the wettest conditions suggesting that to maximize N use, plants needed to grow rapidly and have reasonable yield potential.Assessment of the potential impacts of errors in the values of the input factors indicated that poor estimation of, in particular, yield expectation and soil mineral N before planting could lead to either yield loss or an increased level of potentially leachable soil mineral N at harvest.The research demonstrates the benefits of using computer simulation models to quantify the main factors for which information is needed in order to provide robust N fertilizer recommendations.

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A Threat of Farmers’ Suicide and the Opportunity in Organic Farming for Sustainable Agricultural Development in India

Sustainability ◽

10.3390/su11082400 ◽

2019 ◽

Vol 11 (8) ◽

pp. 2400 ◽

Cited By ~ 4

Author(s):

Karthikeyan Mariappan ◽

Deyi Zhou

Keyword(s):

Organic Farming ◽

Tamil Nadu ◽

Agricultural Development ◽

Small Scale ◽

Conventional Farming ◽

Wide Range ◽

Significant Difference ◽

Small Scale Farmers ◽

The Cost ◽

Input Cost

Agriculture is the main sources of income for humans. Likewise, agriculture is the backbone of the Indian economy. In India, Tamil Nadu regional state has a wide range of possibilities to produce all varieties of organic products due to its diverse agro-climatic condition. This research aimed to identify the economics and efficiency of organic farming, and the possibilities to reduce farmers’ suicides in the Tamil Nadu region through the organic agriculture concept. The emphasis was on farmers, producers, researchers, and marketers entering the sustainable economy through organic farming by reducing input cost and high profit in cultivation. A survey was conducted to gather data. One way analysis of variance (ANOVA) has been used to test the hypothesis regards the cost and profit of rice production. The results showed that there was a significant difference in profitability between organic and conventional farming methods. It is very transparent that organic farming is the leading concept of sustainable agricultural development with better organic manures that can improve soil fertility, better yield, less input cost and better return than conventional farming. The study suggests that by reducing the cost of cultivation and get a marginal return through organic farming method to poor and small scale farmers will reduce socio-economic problems such as farmers’ suicides in the future of Indian agriculture.

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Post-anthesis sink size in a high-yielding dwarf wheat: yield response to grain number

Australian Journal of Agricultural Research ◽

10.1071/ar9770165 ◽

1977 ◽

Vol 28 (2) ◽

pp. 165 ◽

Cited By ~ 36

Author(s):

RA Fischer ◽

I Aguilar ◽

DR Laing

Keyword(s):

Grain Yield ◽

Wheat Yield ◽

Kernel Weight ◽

Yield Response ◽

High Fertility ◽

Grain Number ◽

Wide Range ◽

Carbon Dioxide Fertilization ◽

Sink Size ◽

The One

Experiments to study the effect of grain number per sq metre on kernel weight and grain yield in a high-yielding dwarf spring wheat (Triticum aestivum cv. Yecora 70) were conducted in three seasons (1971–1973) under high-fertility irrigated conditions in north-western Mexico. Crop thinning, shading and carbon dioxide fertilization (reported elsewhere), and crowding treatments, all carried out at or before anthesis, led to a wide range in grain numbers (4000 to 34,000/m2). Results indicated the response of grain yield to changing sink size (grains per sq metre), with the post-anthesis environment identical for all crops each year, and with all but the thinner crops intercepting most of the post-anthesis solar radiation. Kernel weight fell linearly with increase in grain number over the whole range of grain numbers studied, but the rate of fall varied with the season. Grain yield, however, increased, reaching a maximum at grain numbers well above those of crops grown with optimal agronomic management but without manipulation. It was concluded that the grain yield in normal crops was limited by both sink and post-anthesis source. There was some doubt, however, as to the interpretation of results from crowded crops, because of likely artificial increases in crop respiration on the one hand, and on the other, in labile carbohydrate reserves in the crops at anthesis. Also deterioration in grain plumpness (hectolitre weight) complicates the simple inference that further gains in yield can come from increased grain numbers alone.

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A COMPARATIVE ANATOMICAL CHARACTERISTICS OF THE STEMS OF CLIMBING PLANTS IN ARALAM WILD LIFE SANCTUARY, KANNUR

Kongunadu Research Journal ◽

10.26524/krj124 ◽

2016 ◽

Vol 3 (1) ◽

pp. 37-44

Author(s):

Prasanth K.P ◽

Sekaran S

Keyword(s):

Secondary Growth ◽

Life Forms ◽

Tinospora Cordifolia ◽

Piper Nigrum ◽

Supporting Cells ◽

Anatomical Structures ◽

Climbing Plants ◽

Plant Life Forms ◽

Wide Range ◽

Storage Parenchyma

Climbing plants differ from self-supporting plants, such as shrubs and trees, in a range of characteristics. The most notable is the mechanical properties of the stem Comparison of the differentiated anatomical structures recorded in ten species of the climbing plants. The plants selected for the present study are Ampelocissus latifolia, (Vitaceae), Lygodium flexuosum (Lygodiaceae), Centrosema virginianum (Fabaceae), Tinospora cordifolia, (Menispermaceae), Wattakakka volubilis (Asclepiadaceae) Cyclea peltata (Menispermaceae), Calycopteris floribunda (Combretaceae) Pothos scandens (Araceae) Ipomoea separia (Convolvulaceae) and Piper nigrum (Piperaceae). The stems of climbing plants are characterized by the scarcity of supporting cells (fibers) and an increase in the diameter of the xylem vessels. The study con firms that they show a greater diversity of organization than other plant life forms. This anatomical radiation couldprobably not exist without the achievement of a wide range of secondary growth processes. Many dicotyledons, notably those with a climbing habit, show interesting secondary structure which differs from the more usual type described, therefore, sometimes termed anomalous. The variant secondary growth isparticularly widespread in tropical climbers. It is speculated that variant growth can increase stem flexibility, protect the phloem, increase storage parenchyma, aid in clinging to supports, limit physical disruption of vascular tissues during twisting and bending, and promote wound healing after girdling.

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