CAB Reviews 2018 13, No. 055 Q1 IPM for tropical crops: soyabeans E.A. Heinrichs1* and Rangaswamy Muniappan2 Address: 1 IPM Innovation Lab, 6517 S. 19th St., Lincoln, NE, USA. 2 IPM Innovation Lab, CIRED, Virginia Tech, 526 Prices Fork Road, Blacksburg, VA, USA. *Correspondence: E.A. Heinrichs. Email: [email protected] Received: 29 January 2018 Accepted: 16 October 2018 doi: 10.1079/PAVSNNR201813055 The electronic version of this article is the definitive one. It is located here: http://www.cabi.org/cabreviews © CAB International 2018 (Online ISSN 1749-8848) Abstract Soyabean, because of its importance in food security and wide diversity of uses in industrial applications, is one of the world’s most important crops. There are a number of abiotic and biotic constraints that that threaten soyabean production. Soyabean pests are major biotic constraints limiting soyabean production and quality. Crop losses to animal pests, diseases and weeds in soyabeans average 26–29% globally. This review discusses biology, global distribution and plant damage and yield losses in soyabean caused by insect pests, plant diseases, nematodes and weeds. The interactions among insects, weeds and diseases are detailed. A soyabean integrated pest Q2 management (IPM) package of practices, covering the crop from pre-sowing to harvest, is outlined. The effect of climate changes on arthropod pests, plant diseases and weeds are discussed. The history and evolution of the highly successful soyabean IPM programme in Brazil and the factors that led to its demise are explained. Q3 Keywords: Review Methodology: The following databases were searched for relevant articles: Agricola and CAB Abstracts from 1960 on, Plantwise, CABI Invasives, Google Scholar, Google Search, Yahoo Search, EPPO Global Database, Encyclopedia of Life and BugGuide. This was supplemented through personal contacts. Q4 Introduction been used by the food processing industry – in such foods as margarine, shortening, ice cream, salad dressings and Soyabean, one of the oldest food plants, was domesticated mayonnaise. Industry uses smaller amounts in products in northeastern China by 1100 BC. Over the next several including paint, ink, putty, caulking, wallpaper, rubber hundred years the domesticated soyabean (Glycine max) substitutes, adhesives, fire extinguisher foam, electrical spread throughout much of eastern Asia. It grew upright insulation and gasoline (ethanol). The versatile soyabean is a and yielded larger, more digestible seeds. A variety of foods part of everyone’s life in developed countries [1]. was developed from the soyabean, ranging from soyabean The crop is grown on about 6% of the world’s arable land sprouts to steamed raw beans to roasted seeds to soy milk and since the 1970s; the area in soyabean production has to soy sauce to fermented soyabean paste and cake to soy the highest increase compared with any other crop [2]. flour to the commonly eaten curd called tofu (or doufu) [1]. Global soyabean production was 17 million metric tonnes Soyabeans reached the western world by the early 1700s (MMT) in 1960 and increased to 313 MMT in 2015. Future and were first grown in North America by 1804. Benjamin production is expected to increase more than other crops, Franklin appears to have been involved in introducing due to expanded production area and higher yields. soyabeans from France to Philadelphia at that time. The USA, Brazil and Argentina dominate global soyabean A number of varieties were grown and evaluated in the production [2]. These three countries produced 83% United States. (276 MMT) of world production in 2015. Most of the Today, the soyabean crop is one of the most important soyabeans (116 MMT) were produced in the United States, crops worldwide [2]. American soyabean production has with 99 MMT in Brazil and 61 MMT in Argentina. http://www.cabi.org/cabreviews 2 CAB Reviews China and India produce most of the soyabeans grown in on the stage when the injury occurs. Research studies Asia (19 MMT), while only a few are produced in Europe indicate that injury during the vegetative stages is usually and Africa [3]. In the USA, soyabean is third in production not as detrimental to the plant as that during the (maize and wheat are first and second). reproductive stages. The following system is used with ‘V’ representing vegetative stages and ‘R’ reproductive stages: Nutritional Value of Soyabean Soyabean plays an important role in food security because it Vegetative stages Reproductive stages is a highly nutritious crop. In 100 g (raw green soyabeans), VE: emergence R1: beginning bloom soyabeans supply 446 calories and have 9% water, 30% VC: cotyledon + unfolding unifoliate R2: full bloom carbohydrates, 20% total fat and 36% protein. Soyabeans V1: 1st node trifoliate R3: beginning pod V2: 2nd node trifoliate R4: full pod are an exceptional source of essential nutrients, providing V3: 3rd node trifoliate R5: beginning seed in a 100-g serving (raw) high contents of the daily value V4: 4th node trifoliate R6: full seed (DV) especially for protein (36% DV), dietary fibre (37%), V5: 5th node trifoliate R7: beginning maturity iron (121%), manganese (120%), phosphorus (101%) and Vn: Nth node trifoliate R8: full maturity several B vitamins including folate (94%). High contents exist for vitamin K, magnesium, zinc and potassium [4]. Because the soyabean crop is highly nutritious and Because soyabean response to insects is dependent on versatile it offers resources to address world food issues growth stage, economic thresholds vary with the stage. through current and future utilization practices. Future Therefore, it is important that growers recognize these production is expected to increase due to increased developmental stages. demand and with the application of newer genomic technologies the crop has enormous potential to improve dietary quality for people throughout the world whether Cropping Systems consumed as a vegetable crop or processed into various soyabean food products [2]. Most soyabeans are grown in a crop rotation sequence, typically with a non-legume such as maize, small grains, sorghum or cotton. The yield of the non-legume is Soyabean Types and Growth Phases improved because of the left-over nitrogen from the soyabean root nodules. In addition, disease, pest and To effectively manage soyabean pests, in an integrated pest weed problems are reduced in rotations compared with management (IPM) context, it is important to be familiar growing one crop continuously [1]. with the soyabean plant and its growth throughout the crop Soyabeans are also often grown in a double-cropping season. Many decisions that a soyabean grower will make system, with two crops being grown in the same year. depend on the type of soyabean variety and the growth Winter wheat followed by soyabeans is the most common; stage of the plant [5, 6]. snap beans or peas followed by soyabeans is another. Soyabean varieties are grouped into 13 maturity groups, depending on the climate and latitude for which they are adapted. These maturity groups are given numbers, with numbers 000, 00, 0 and 1 being adapted to Canada Constraints to Soyabean Production and the northern United States, and numbers VII, VIII and IX being grown in the southern USA. Group X is There are a number of abiotic and biotic constraints that tropical. Associated with maturity group is the manner in that threaten soyabean production by directly reducing which the stem grows and flowering is initiated. Most seed yields and/or seed quality. Abiotic constraints include northern America adapted cultivars have an indeterminate extremes in nutrients, temperatures and moisture. These growth pattern; the terminal bud continues its vegetative reduce production directly, but also indirectly through activity throughout the growing season and the plant increase in pathogens and pests [2]. Biotic constraints continues to add foliage after flowering. Most cultivars in consist primarily of insects, pathogens, nematodes and the southern USA and the tropics have a determinate weeds. growth pattern; vegetative growth ceases after flowering. Pathogens and pests of soyabeans infect and/or attack all A primary difference between the two, which influences parts of the soyabean plant from roots to seed pods [7]. IPM decisions, is that the indeterminate cultivars have the The extent of economic damage depends on the type of ability to compensate for leaf loss. pest/pathogen, plant tissue being attacked, number of plants For the purpose of managing soyabean pests, growth affected, severity of attack, environmental conditions, host stage is the most important criterion because the relation- plant susceptibility, plant stress level and stage of plant ship between insect injury and crop damage is dependent development [8]. http://www.cabi.org/cabreviews E.A. Heinrichs and Rangaswamy Muniappan 3 Biotic constraints can result in significant negative coleopteran grubs (larvae) and the seedcorn maggot; impacts on yield. Crop losses to animal pests, diseases (2) holes in leaves or skeletonized leaves due to the and weeds in soyabeans average 26–29% globally [9, 10]. feeding of defoliating insects primarily Lepidoptera and Weeds are the predominant pest group in soyabeans. Coleoptera; (3) leaves are distorted and discoloured due to Weed competition causes 37% loss of attainable pro- the feeding of aphids and spider mites and (4) pods are duction while fungal pathogens, bacterial pathogens, viruses damaged by the feeding of the bean leaf beetle, pod borers and