Artificial intelligence and Impact of Climate Change on Insect-Pests Behaviour

Artificial intelligence is used to describe machines that mimics cognitive functions that humans associate with the human mind such as learning and problem solving. It has played an important role in various sectors of agriculture. Insect pests are one of the major problems in the agricultural field.

The Food and Agriculture Organization (FAO) reported that these pests cause between 20 and 40 percent loss of global crop production every year.

The pest infestation costs the global economy around $220 billion and invasive insects around US $70 billion annually. Different pesticides have been used by farmers widely to increase the quality as well as storage life of crops. But the continuous and indiscriminate use of these pesticides resulted in the environmental contamination and potential high-risk diseases such as cancer, extreme respiratory and genetic diseases, and foetal death eventually. To detect plant pests at an early stage and save undesirable consumption of pesticides, advanced technical solutions are needed in agriculture. Invasive pests like fall army worm (Spodoptera frugiperda) in corn and Rugose spiraling whitefly in coconut (Aleurodicus rugioperculatus Martin) have recently threatened cultivated crops in the country and cause extensive damage.

The Indian Agricultural Research Institute–Natural Bureau of Agricultural Insect Resources estimated the intensity of infestation of falarmywormrm to the tune of 9–62% with an economic yield loss of 34%. The plant protection measures are to be taken on a community basis so as to ensure effective management of pests. Smart agriculture has been recently introduced to apply Artificial Intelligence (AI) techniques for precision control of plant insect pests.

Climate change is a major challenge for agriculture and food security, Climate change may cause sudden reductions in agricultural productivity. Egypt is considered as a one of the worst-weather countries which is affected be climate change: including high rising temperatures, erratic rainfall, sandstorms and extreme heat. The production of the strategic crops will suffer from significant reduction from 10% to 60% by the middle of the century (2050) due to temperature increases. Intelligent Decision Support System IDSS provides the good solution to minimize the effects of climate change in an intelligent manner and provides the required solutions to successfully penetrate this highly competitive and regulatory challenging environment. These solutiondependds on GIS to determine location and its properties, climate prediction model, knowledge base model in agricultural domain as plants, insects and diseases using domain expert knowledge extraction, data mining, machine learning and fuzzy logic to obtain a fast and high accuracy solutions.

Climate change is the most important, and the most complex, global environmental issue to-date. Effects of green house gases and climatic changes are already evident from the rising climatic temperature, recurrent droughts, erratic rains, flooding and submergence etc. Insects may be the first predictors of climate change. Such changes in climatic conditions could profoundly affect the population dynamics and the status of insect pests of the crops. As per the last assessment report from the Intergovernmental Panel on Climate Change (IPCC), If no climate policy interventions are made there will be an increment in mean temperature from 1.1 to 5.4 o C and atmospheric CO2 concentration rise 540 to 970 ppm @ 2µl/yr towards the year 2100 (IPCC, 2007).

Climate change related factors like rise in temperature, changes in precipitation patterns, milder and shorter winters, rise of sea levels and increased incidence of extreme weather events can directly influence insects by affecting their rate of development, reproduction, distribution, migration and adaptation. In addition, indirect effects can occur through the influence of climate on the insect’s host plants, natural enemies and interspecific interactions with other insects. The impacts include changes in phenology, distribution and community composition of ecosystem that finally leads to extinction of species (Walther et al., 2002).

Effects of Climate Change on Insect growth & behavior:

It has been estimated that with a 2°C temperature increase insects might experience one to five additional life cycles per year Eg; 1-3 0 C rise in temperature causes expansion of European corn borer additional generations in all the regions of its occurrence. At higher temperatures, aphids have been shown to be less responsive to the aphid alarm pheromone they release when under attack by insect predators and parasitoids – resulting in the potential for greater predation. At higher temperature of 36°C, 38°C the net reproductive rate was higher and the generation time was shorter compared to 30°C in YSB and BPH respectively (Ramya et al., 2012).

Longer growing seasons with warmer climate will enable insect pests such as grasshoppers to complete a greater number of reproductive cycles during spring, summer and autumn. Shorter dry spell lead to higher infestation of mites and mealy bug. An increase of 20 C will cause reduction in the generation turnover of the aphid, Rhopalosiphum padi (L.) For every 10 C rise in winter temperatures will reduce the adult mortality of green bug, Nezara viridula by 15%. An increase of 30 C in mean daily temperature would cause the carrot fly, Delia radicum (L.) to become active a month earlier than at present (Collier et al., 1991).

Climate change effect on migratory insects:

Migratory insects (corn earworm in northern parts of the northeast) may arrive in the Northeast earlier, or the area in which they are able to overwinter may be expanded. Temperature may change gender ratios of some pest species such as thrips potentially affecting reproduction rates. Higher summer temperatures cause higher no. of migration in Lepidopteran insects by increasing flight, higher mating and egg production. But heavy downpour decreases Lepidopteran population. Potato leafhoppers arrive on an average of 10 days earlier than in the early 1950s, and their infestations are more severe in the warmest years. Spring migration in aphid, M. persicae advances by 14 days for every 10 C rise in temp (Harrington et al., 2001).

Climate change effect on insect distribution:

More than 1700 Northern Hemisphere species have exhibited significant range shifts @ 6.1 km per decade towards the poles (or 6.1 m per decade upward). In California, 70% of 23 butterfly species now start their first flight about 24 days earlier than they used to do 31 years ago Spruce budworm, Choristoneura fumiferana under climate change they will shift towards the poles. Green Stinkbug, Nezara viridula, expanded its range northwards by 85 Km @ 19 Km/decade in Japan with mean increase of 1.3-1.90 C temp. in Jan-Feb. 1- 3 0 C rise in temperature causes expansion of European corn borer distribution upto 1220 Km Northwards. Sachem skipper, Atalopedes campestries expanded its range from northern California to washington from 1950’s to 1990 with a 2-4 0 C rise in temp. Study conducted on 1100 insect species, climate changes due to global warming may cause 15-37% of those species to extinct by 2050 (Thomas et al., 2004).

Invasion into new regions:

Heliothis armigera- serious pest in Portugal and Spain migrated to Denmark Norway, Sweedan, Slovenia and Netherlands during summer by extending it’s range by 590N in Nothern Hemisphere. The African plain tiger butterfly, Danaus chrysippes, completely established its population in Southern Spain between 1980 -1990. Southern Green Stink Bug, Nezara viridula and Leptocorisa chinensis Tropical and sub tropical countries in the world to Northward range shift to the temperate zone.

Climate change-Insect phenology:

With increased temperatures, it is expected that insects will pass through their larval stages faster and become adults earlier and an increase in the length of the flight period.

1. Changes in butterfly phenology have been reported in UK, where 26 of 35 species have advanced their first appearance.

2. First appearance for 17 species in Spain has advanced by 1-7 weeks in just 15 years.

3. Four Mediterranean insect species viz. butterfly, bee, fly and beetle indicated changes in their first appearance date over the last 50 years, @ 5.1 days/decade which was correlated with increases in spring temperature. (Gordo and Sanz, 2005).

Climate change and pest outbreaks:

Changes in climatic variables have led to increased frequency and intensity of outbreaks of insect-pests. 

• Outbreak of sugarcane woolly aphid Ceratovacuna lanigera Zehntner in sugarcane belt of Karnataka andv Maharashtra states during 2002-03 resulted in 30% yield losses.

• Increased frequency, intensity and outbreaks of fruit fly in cucurbits particularly due to high temperaturev and high RH.

• Increased infestation of rice crop by swarming caterpillar, hispa, stem borer and bacterial blight.

• Mirid bug Ragmus spp. on cotton appeared in epidemic form Dharwar (Karnataka) and Coimbatore (Tamil Nadu) on cotton.

• Spodoptera litura on soybean outbreak during 2005 vidarbha region of Maharashtra.

Elevated CO2 and Pest Population:

Generally CO2 impacts on insects are thought to be indirect - impact on insect damage results from changes in the host crop. A rise in CO2 generally increases the carbon to nitrogen ratio of plant tissues thereby reducing the nutritional quality for protein limited insects diluting the nitrogen content of the tissues. The expected reactions from herbivores to the increase in carbon to nitrogen ratio are compensatory feeding, concentrations of defensive chemicals in plants and competition between pest species. Insects may accelerate their food intake to compensate for reduced leaf nitrogen content. 

• Bollworm larvae feeding on elevated CO2-grown pea plants, Pisum sativum at 700 ppm were significantly smaller than those reared on plants grown under ambient-CO2 conditions.

• Eelevated CO2 could prolong the larvae duration and delay the development of cotton bollworm larvae.

• Egg stage and first-instar larval stage of Frankliniella occidentalis (Pergande), and the pupal duration of Cnaphalocrocis medinalis (Guenee) were significantly decreased in an elevated CO2 concentration Treatment.

• Soybeans grown in elevated CO2 atmosphere had 57% more damage from insects (primarily Japanese beetle, potato leafhopper, western corn rootworm and Mexican bean beetle) than those grown in today’s atmosphere. Increases in the levels of simple sugars in the soybean leaves may have stimulated the additional insect feeding (Hamilton et al., 2005).

How changes in precipitation will affect insects?

Some insects are sensitive to precipitation and are killed or removed from crops by heavy rains. Other insects such as pea aphids are not tolerant of drought. As with temperature, precipitation changes can impact insect pest predators, parasites, and diseases resulting in a complex dynamic.

It is predicted that more frequent and intense precipitation events may have negative impacts on insect pest population. Similar to temperature, precipitation changes can impact insect pest predators, parasites and diseases resulting in a complex dynamic manner. Increase in rainfall will largely affect the species particularly the beetles with poor dispersal capabilities, which will limit their ability to expand their home. Heavy down pour causes reduction in pest population of Lepidopterans.

Effect of Increased ozone on troposphere

Enriched O3 atmospheres - increased activity of defense-related plant enzymes, production of phenolics controlled by the shikimic acid pathway, such as tannins, and decreasing the production of glycosides due to competition between branches of the pathway for substrates.

Holton et al., 2003 showed that the forest tent caterpillar, Malacosoma disstria (Hubner) (Lepidoptera: Lasiocampidae) reared on plants grown under increased O3 conditions were larger and developed faster.

CONCLUSION: 

• The preponderance of evidence indicates that there will be an overall increase in the number of outbreaks of a wider variety of insects and pathogens.

• A complete understanding of the effects of these changes on the interactions between insects and their host plants will be achieved only after controlled, factorial experiments can be designed and followed over longer periods of time to predict future trends.

• Predicting the impact of climate change on insects is a very complex exercise and a one that involves a great deal of modeling.

• The best economic strategy for farmers to follow is to use integrated pest management practices to closely monitor insect and disease occurrence. Keeping pest and crop management records over time will allow farmers to evaluate the economics and environmental impact of pest control and determine the feasibility of using certain pest management strategies or growing particular crops.

REFERENCES:

[1].Collier, R.H., Finch, S., Phelps, K and Thompson, A.R. 1991. Possible impact of global warming on cabbage root fly (Delia radicum) activity in the UK. Annals of Applied Biology, 118: 261-271.

[2].Gordo, O and Sanz, J.J. 2005. Phenology and climate change: a long-term study in a Mediterranean locality. Oecologia. 146: 484–495.

[3].Hamilton, J.G., O. Dermody, M. Aldea, A.R. Zangerl, A. Rogers, M.R. Berenbaum, and E. Delucia. 2005. Anthropogenic Changes in Tropospheric Composition Increase Susceptibility of Soybean to Insect Herbivory. Envirn. Entomol. 34:2 479-485.

[4].Harrington, R., R, Fleming, I. P. Woiwood. 2001. Climate change impacts on insect vulnerability of aphids to natural enemies. Ecological Entomology. 22:366-368.

[5].Holton, M.K, Lindroth, R.L and Nordheim, E.V. 2003. Foliar quality influences tree-herbivore-parasitoid interactions: effects of elevated CO2, O3, and plant genotype. Oecologia 137: 233-244.

[6].Intergovernmental Panel on Climate Change. 2007. Climate Change 2007: The Physical Science Basis. Rep.Work. Group I Intergov. Panel Climate Change, IPCC Secr., Geneva, Switzerland. (http://www.ipcc.ch/).

[7].M. Ramya, J.S. Kennedy, V. Geetha Lakshmi, A. Lakshmanan, N. & Nagothu Udaya Sekhar (Bioforsk). 2012. Impact of elevated temperature on major pests of rice. CLIMARICE technical Brief.

[8].Thomas C.D., Cameron, A., Green, R.E., Bakkenes, M., Beaumont, L.J., Collingham, Y.C., Erasmus, B.F.N,, Fereira de Sigueira, M., Grainger, A., Hannah, Hughes L, Huntley, B., Jaarsveld van A.S., Midgley G.F., Miles, L., Ortega-Huerta, M.A, Townsend, P.A Phillips, O.L and Williams S.E. 2004. Extinction risk from climate change. Nature. 427: 145–148.

[9].Walther G.R, Post, E., Convey, P., Menzel, A., Parmesan and C, Beebee T.J.C. 2002. Ecological responses to recent climate change. Nature. 416: 389-395.

Authors

Dr. Hadi Husain Khan¹, Dr. Mohd. Monobrullah², Dr. Anjani Kumar³, Dr. Ram Eshwar Prasad⁴, Dr. Kinkar Kumar⁵ and Lalta Prasad Verma⁶

¹Scientist (Plant Protection), Krishi Vigyan Kendra, Sitamarhi - 843320 (Bihar), India.

²Principal Scientist, Division of Crop Research, ICAR-RCER, Patna - 800014 (Bihar), India.

³Director, ICAR-ATARI, Zone-IV, Patna- 801506 (Bihar), India.

⁴Senior Scientist & Head, Krishi Vigyan Kendra, Sitamarhi - 843320 (Bihar), India.

⁵Scientist (Animal Science), Krishi Vigyan Kendra, Sitamarhi - 843320 (Bihar), India.

⁶SRF (NICRA Project), Krishi Vigyan Kendra, Sitamarhi - 843320 (Bihar), India.