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Kerala Agricultural University, Thrissur
The history of agricultural education in Kerala can be traced back to the year 1896 when a scheme was evolved in the erstwhile Travancore State to train a few young men in scientific agriculture at the Demonstration Farm, Karamana, Thiruvananthapuram, presently, the Cropping Systems Research Centre under Kerala Agricultural University. Agriculture was introduced as an optional subject in the middle school classes in the State in 1922 when an Agricultural Middle School was started at Aluva, Ernakulam District. The popularity and usefulness of this school led to the starting of similar institutions at Kottarakkara and Konni in 1928 and 1931 respectively.
Agriculture was later introduced as an optional subject for Intermediate Course in 1953. In 1955, the erstwhile Government of Travancore-Cochin started the Agricultural College and Research Institute at Vellayani, Thiruvananthapuram and the College of Veterinary and Animal Sciences at Mannuthy, Thrissur for imparting higher education in agricultural and veterinary sciences, respectively. These institutions were brought under the direct administrative control of the Department of Agriculture and the Department of Animal Husbandry, respectively. With the formation of Kerala State in 1956, these two colleges were affiliated to the University of Kerala. The post-graduate programmes leading to M.Sc. (Ag), M.V.Sc. and Ph.D. degrees were started in 1961, 1962 and 1965 respectively.
On the recommendation of the Second National Education Commission (1964-66) headed by Dr. D.S. Kothari, the then Chairman of the University Grants Commission, one Agricultural University in each State was established. The State Agricultural Universities (SAUs) were established in India as an integral part of the National Agricultural Research System to give the much needed impetus to Agriculture Education and Research in the Country. As a result the Kerala Agricultural University (KAU) was established on 24th February 1971 by virtue of the Act 33 of 1971 and started functioning on 1st February 1972. The Kerala Agricultural University is the 15th in the series of the SAUs.
In accordance with the provisions of KAU Act of 1971, the Agricultural College and Research Institute at Vellayani, and the College of Veterinary and Animal Sciences, Mannuthy, were brought under the Kerala Agricultural University. In addition, twenty one agricultural and animal husbandry research stations were also transferred to the KAU for taking up research and extension programmes on various crops, animals, birds, etc.
During 2011, Kerala Agricultural University was trifurcated into Kerala Veterinary and Animal Sciences University (KVASU), Kerala University of Fisheries and Ocean Studies (KUFOS) and Kerala Agricultural University (KAU).
Now the University has seven colleges (four Agriculture, one Agricultural Engineering, one Forestry, one Co-operation Banking & Management), six RARSs, seven KVKs, 15 Research Stations and 16 Research and Extension Units under the faculties of Agriculture, Agricultural Engineering and Forestry. In addition, one Academy on Climate Change Adaptation and one Institute of Agricultural Technology offering M.Sc. (Integrated) Climate Change Adaptation and Diploma in Agricultural Sciences respectively are also functioning in Kerala Agricultural University.
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ThesisItem Open Access Genetic studies in red gram (eafanui caiaixL)(Department of Agricultural Botany, College of Horticulture, Vellanikkara, 1988) Radhakrishnan, V V; KAU; Narayanan Namboodiri, K NThesisItem Open Access Evaluation of selections and hybrids of Vetiver (Vetivena zizanieides (Linn ) Nash)(Department of Agricultural Botany, College of Horticulture, Vellanikkara, 1991) Radhakrishnan, G R; Viswanathan, T VThesisItem Open Access Genetic variability and path coefficient studies on fodder yield and its components in oats( Avena sativa. L.)(Department of Agricultural Botany, Rajasthan college of Agriculture, University of Udaipur, 1976) Sukumaran, Nair PThesisItem Open Access Genetic studies in sweet potato (ipomoea batatas(l.)lam.) a biometric approach(Department of Agricultural Botany, College of Agriculture, Vellayani, 1979) Joseph, C A; KAU; Mary George, KIn a varietal evaluation of 40 varieties of sweet potato all the 15 characters studied showed highly significant differences among the varieties. This was also expressed in the higher phenotypic and genotypic coefficients of variation. The high degree of variability especially in tuber characters offers scope for recombining desirable genes from different varieties. Tuber yield showed significant positive correlation with number of tubers, tuber diameter and harvest index, and significant negative correlation with internode length, vine length and top weight. Path-coefficient analysis revealed that among the first order components of tuber yield, tuber diameter, length and number and top weight had high positive direct effects while leaf area index had a negative direct effect. A comparison of the direct and indirect effects of first and second order components revealed that while selecting for high yielding types, a balanced approach may be adopted with regard to the different yield attributes. Genetic divergence in the available germ plasm was estimated using the Mahalanobis' D2 statistic and based on this the 40 varieties were grouped into 12 clusters. The number of verities in each cluster ranged from one to eight. The divergence between different clusters was not always due to divergence in the same set of characters but a combination of different sets of characters. Out of the fifteen characters studied seven viz., tuber diameter, vine length, number of branches, number of tubers, tuber yield, top weight and number of leaves accounted for more than 80 per cent of the divergence in the material. Canonical analysis also more or less confirmed the grouping of the verities made by Tocher's method. Eight varieties selected on the basis of genetic divergence were used for progeny studies. All these varieties were found to be completely self-incompatible. It is observed that time of pollination markedly affected fruit and seed set. Maximum fruit and seed set was obtained between 7 and 7.30 a.m. And it progressively decreased as time passes. The weather conditions prevailing during the period of anthesis and pollination also influenced fruit and seed set. Maximum, minimum and mean temperature had significant negative correlation with both fruit and seed set. Path-coefficient anaysis revealed that most of the weather elements studied had negative direct effect on fruit and seed set. The total contribution of weather elements alone on fruit and seed set worked out to 40 and 32.5 percent respectively and hence any study on incompatibility and sterility in sweet potato may be conducted under controlled environmental conditions for reliable results. Genetic analysis of quantitative characters was done utilising line x tester and open pollinated progenies of the eight selected varieties. In the open pollinated progenies, existence of non- additive and environmental effects were observed in top weight, vine length, tuber diameter and leaf area index, and additive effects in number of leaves, number of tubers and tuber yield. In the line x tester progenies, additive variance was high compared to non- additive components in all the characters except the number of branches. The regression coefficients of progenies on male and mid- parental values were significant in seven out of ten characters in the line x teater progenies and in four characters on female parental values in the open pollinated progenies. The standardised regression coefficients reduced the magnitude and variability in the regression coefficients to some extent. The estimates of broad sense heritability from the varietal evaluation was higher in magnitude for most of the characters than the estimates of narrow sense heritability obtained from components of variance in open pollinated and line x tester progenies. Tuber yield showed 70.61 and 43.65 per cent heritability from the components of variance analyses in the open pollinated and line x tester progenies respectively, while number of tubers showed 82.75 and 70.07 per cent heritability. The variance between males was significant in respect of top weight, vine length, number of leaves, number of tubers, tuber diameter, leaf area index and harvest index, while the variance between females was significant only in tuber length. Significant reciprocal differences were observed in top weight, number of tubers, leaf area index and harvest index. With respect to general combining ability significant positive effects were observed in number of tubers in the varieties J.29 and H.42, tuber length in Palchakram and H.42, tuber diamter in IB.40 and Chakkaravalli and harvest index in J.29 and Palchakram. Significant heterotic effects were observed in a number of vine and tuber characters in both hybrid and open pollinated progenies. Seven hybrid progenies showed significant increase in tuber yield which ranged from 31.25 to 84.63 per cent over the higher parental values. Both hybrid and open pollinated progenies gave heterotic combinations for economic characters. The varieties which gave heterotic progenies by open pollination have performed well in certain hybrid combinations also. Considering the difficulties in the large scale hybridization and production of hybrid seedling, it is suggested that open pollination in selected varieties especially good combiners can be adopted as a quick and efficient method for varietal improvement in sweet potatoThesisItem Open Access Induced chemical mutagenesis in Rose under in vitro culture(Department of Agricultural Botany, College of Agriculture,Vellayani, 1991) Uma, B; KAU; Krishnan Nair, NThe present investigation entitled “Induced chemical mutagenesis in rose (Rosa chinensis) under in vitro culture” was carried out in the Tissue Culture Laboratory attached to the Horticultural Department, College of Agriculture, Vellayani during 1989-90. The main objectives of the experiment were to standardize a suitable culture medium for the growth and development of axillary buds and to standardize a successful method of chemical mutagenesis in rose under in vitro culture using the most potent chemical mutagen, ethyl methane sulphonate. The standardization of hormone levels in the culture medium (ms) was done at three stages of explant development viz. culture establishment, axillary bud proliferation and in vitro rooting. Surface sterilization of axillary buds were standardized by using mercuric chloride selecting out three concentrations 0.06, 0.08 and 0.1 per cent and 3 periods of treatment 5, 10 and 15 minutes. The axillary buds used were of 4 maturity stages ie. Axillary buds at the time of flower harvest and 2, 4 and 6 days after flower harvest. The various concentrations of ethyl methane sulphonate tested include 0.125, 0.25, 0.375 and 0.5 per cent. Two methods of mutagen treatments were tried ie. direct treatment and cotton swab method. In the direct treatment the axillary buds were subjected to EMS treatment at different periods treating the buds at the time of culturing, 2 days after culturing, 4 days after culturing and 6 days after culturing. In the cotton swab method buds were treated with EMS in the plant itself at various stages ie. at the time of flower harvest and 2,4 and 6 days after flower harvest. Surface sterilization of axillary buds was found to be most successful with mercuric chloride at 0.08 per cent for 15 minutes of the various levels of hormonal combinations tested BAP 2 mg/1 +2.4-D 1 mg/1 was found to be the best for culture establishment and BAP 2 mg /1 +GA 1mg/1 for shoot proliferation. Maximum rooting was obtained in full strength MS medium supplemented with IAA 2 mg/1 of the two methods of mutagen treatments tried direct treatment of axillary buds with EMS was not found to be effective as the buds turned brown and no further development occurred. In the cotton swab method, lower concentrations of EMS (0.125 and 0.25 per cent) gave a better performance based on days taken for bud take multiple shoot production and rooting percentage. A decrease in survival percentage was noted with increase in mutagen concentration. Higher concentration of EMS (0.375 and 0.5 per cent) curbed multiple shoot production in buds excised at the time of flower harvest and delayed multiple shoot production in other stages. The percentage cultures showing rooting and the number of roots/shoot also decreased with increase in concentration of EMS. Increase in maturity of buds also delayed multiple shoot production and decreased rooting percentage of the 4 stages of buds used for in vitro culture, buds excised at the time of flower harvest was found to be the best. But mutagen treatment retarded their performance. For mutagen treatment buds excised 4 days after flower harvest was found to be best followed by buds excised 2 days after flower harvest. Buds excised 6 days after flower harvest showed a poor performance in the normal and treated populations. The experiment clearly demonstrated that induced mutagenesis in rose can be successfully done adopting in vitro culture techniques.ThesisItem Open Access Genic manipulations in sweet potato adopting induced mutations(Department of Agricultural Botany, College of Agriculture,Vellayani, 1989) Suma Bai D I; Krishnan Nair NAn experiment was conducted at the Department of Agricultural Botany, College of Agriculture, Vellayani during 1987-1989 for genetic manipulations in sweet potato through gamma ray induced mutagenesis for increased variability and to isolate out genotypes having wider adaptability and better performance. Stem cuttings of 8 to 10 cm length bearing two nodes each, taken from fifteen sweet potato varieties were used for radiosensitivity analysis. Gamma irradiation was done by a 60 Co gamma cell unit installed in the Radio Tracer Laboratory of Kerala Agricultural University, Trichur. The material was subjected to exposure of 2-10 kR at intervals of 2 kR. The chosen dose rate was 0.162 MR/h. The direct effect of doses on the material was assessed on the basis of days to start sprouting, days to complete sprouting, sprouting percentage, vine length, branch and tuber number and weight of tubers per vine. The exposures above 4 kR caused lethality in the majority of the varieties and hence comparative analysis for ratiosensitivity was assessed at the 2 kR level. The gamma ray exposed population started sprouting late. The days taken for completion of sprouting were also more in all the varieties. Gamma rays, in addition, reduced the sprouting percentage. The percentage lethality varied depending on variety. The vine length and number of branches per vine also varied from variety to variety. They were found to be comparatively less in treated population. The tuber number and weight of tubers per vine were found to be significantly increased by gamma irradiation at 2 kR. Based on the above observations the fifteen varieties were classified into three, viz. low, medium and high radiation sensitive categories. Induced mutagenesis was done in continuation with the radiosensitivity analysis using three varieties, each selected from the low, medium and high radiation tolerant groups. The planting materials selected for gamma irradiation included fresh cuttings, rooted cuttings and rooted tubers which were exposed to radiation at a range of 500 – 2500 r, at 500 r intervals. The dose rate was 0.162 MR/h. The irradiated materials along with the control were planted on the subsequent day. In vM1 generation the direct effect of gamma rays was assessed based on days taken to start sprouting, days taken to complete sprouting, sprouting percentage, lethality on the 30th day of planting and at harvest, vine length, branch number per vine, fresh weight of vine, tuber number per vine, weight, length, girth and volume of tuber and tuber yield per vine. From vM1 plants 3-4 noded cuttings were taken from the basal, middle and top portions for raising vM2 generation. VM3 and vM4 generations were also raised in the same manner. In vM2, vM3 and vM4 generations the yield parameters were analysed in detail. Classification of the phenotypes and frequency analysis were also done. The salient findings of the experiment are the following: There was a delay in sprount initiation and for completion of sprouting caused by gamma ray exposure. A decrease in sprouting percentage and an increase in lethality were noticed under higher levels of exposures. Similarly a reduction in vine length and branch number per vine were found at higher exposures. The fresh weight of vine was reduced and the tuber number increased at higher exposures. There was an increase in mean tuber weight, length, girth, volume and tuber yield per vine at higher exposures. All the exposures and the different modes of treatment induced phenotypic variants both in negative and positive directions. Positive variants were in higher frequency in later generations. Irradiation of rooted cuttings was found to be more economical or beneficial compared to fresh cuttings and rooted tubers. The study enabled to isolate out two promising types, one each from S5 and Bhadrakalichuvala. These mutants outyielded the control and are being multiplied by vine cuttings for farm trials in different agroecological milieus of the State.ThesisItem Open Access Variety Sensitivity Analysis in Cucumis melo L. using Gamma Rays and Ethyl Methane Sulphonate(Department of Agricultural Botany, College of Agriculture,Vellayani, 1990) Nelson Lopez; KAU; Mercy, S TThe effect of gamma rays and 'EMS on ten Cucumis melo L. varieties was studied in the M1 generation. Germinability of seeds was not significantly affected by the different mutagen doses. However in general germination percentage decreased in varieties Panavalli, Attenganam local, Lucknow Sweet, Verma Surprise and Punthala local with gamma ray treatment while in Mudikode local, Pulliporan, Vellanad local and Co-1 germinability was better. EMS treatments in Mudikode local, Hara Madhu, Pulliporan, Puthala local and Co-1 resulted in decreased germination percentage. Significant delay in completion of germination compared to control was observed in different levels of gamma ray treatments in some of the varieties while early germination was noted in some others. Survival percentage, in general, was reduced with mutagen treatment in most of the varieties. Chlorophyll chimeras were noticed in both mutagen treatments. Morphological variations observed included leaf and fruit abnormalities. In general the lower doses of gamma rays resulted in early flowering of male flowers while 30 kR treatment resulted in delayed male flowering. Among EMS treatments, 1.0% and 2.0% treatments in general resulted in a delayed production of first male flower. In the case of appearance of first female flower a significant delay was observed in the higher doses of gamma ray treatments in Co-1 and Attenganam local while a significantly early appearance of first female flower was noted with lower doses of gamma ray treatments in Mudikode local, Lucknow Sweet and Pulliporan. The 1.5 % and 2.0% EMS treatments in general produced first female flower earlier than control and 1.0% treatment. In most of the varieties the EMS treatments in general resulted in the apperance of the first male flower at lower nodes compared to control. EMS treatment induced appearance of first female flower at lower nodes than gamma ray treatment. Increase in sex ratio (male to female) due to some of the EMS treatments was observed in some varieties while a decrease was observed in others. Irradiation with higher doses of gamma rays caused decreased sex ratio in Panavalli, Lucknow Sweet, Hara Madhu, Pulliporan and Punthala local. In general in all varieties there was reduction in pollen and seed fertility with increase in dose of gamma rays and EMS except 10 kR gamma ray treatment and 1.5% EMS treatment where a slight increase in seed fertility was noticed. Different varieties showed differential response to different levels of gamma rays and EMS for number of fruits produced per plant and also for lenght and girth of fruit. Higher doses of gamma rays in Mudikode local, Co-1 and Pulliporan recorded greater fruit weight compared to control while 30 kR treatment in Panavalli and Punthala local recorded lower fruit weight compared to control. In Mudikode local, Panavalli, Vellanad local and Co-1 irradiation of gamma ray in general resulted in significantly lower yields than their control while in Attenganam local gamma ray irradiation resulted in significantly increased yield compared to control. Significantly lower fruit set compared to control occured in 20 kR treatment in Panavalli, Punthala local, Pulliporan and Co-1 whereas 10 kR treatment in Lucknow Sweet and Vellanad local resulted in a significant increase in fruit set. Lower levels of EMS treatments in Hara Madhu, Co-1, Pulliporan and Panavalli induced significantly lower fruit set compared to control. Irradiation with gamma rays resulted in significantly lower number of seeds compared to control in Mudikode local and Punthala local while in Pulliporan greater number of seeds than control was produced due to gamma ray treatment. In Co-1 and Attenganam local, 2.0% EMS treatment resulted in a significant reduction in 100 seed weight while lower levels of EMS treatments in Lucknow Sweet resulted in a significant increase in 100 seed weight compared to their control. The 10 kR treatment of all varieties in general resulted in slight decrease in mean length of main vine compared to control whereas the higher levels of gamma rays resulted in slight increase in mean length of main vine. In general the 2.0% EMS treatment of most of the varieties induced slight reduction in mean length of main vine while the lower levels of EMS resulted in slight increase in mean length of main vine compared to control.ThesisItem Open Access Collection cataloguing and evaluation of rouwolfia spp.(Department of Agricultural Botany, College of Horticulture,Vellanikkara, 1993) Narayanan, A K; KAU; Luckins Babu, CA study on 'Collection, cataloguing and evaluation of Rauwolfia spp' was conducted in the Department of Agricultural Botany, College of Horticulture, Vellanikkara during 1991-93, with the objectives of understanding the distribution pattern of various species of Rauwolfia in Kerala, detailed descriptive study of the morphological and anatomical characters of the different species of Rauwolfia and a preliminary comparative evaluation study for the total alkaloids in roots and the chlorophyll content of aerial parts. Survey of 10 geographic locations of Kerala from North to South was conducted and four species of Rauwolfia were collected. Nine ecotypes of R. Serpentina and four ecotypes of R. tetraphylla were also collected. Different species were compared based on 60 morphological characters, 15 anatomical characters and three characters of pollen grains. Evaluation for total root alkaloids was done using chloroform as solvent and determination of total chlorophyll content was done using acetone as solvent. The study on distribution aspects showed that R. serpentina was widely distributed in Kerala but the frequency of occurrence was low, while R. tetraphylla was widely distributed in non-forest areas only, with a higher frequency of occurence. R. densiflora and R. beddomei are in a state of near extinction while R. micrantha was almost disappeared from Kerala. Morphological and antomical characters and the morphology and viability of pollen grains showed wide variability among different species of Rauwolfia. Characters in addition to that available in the literature, for identifying the four species of Rauwolfia are suggeated. It is seen that chances are there for the occurence of higher ploids of the same species having higher alkaloid content, in Rauwolfia. Total alkaloid content of roots, chloroform extract and total chlorophyll content of aerial parts varied with different species and ecotypes of Rauwolfia. The conditions for the higher root alkaloid production in R. sepentina may not be favourable for the alkaloid production in R. tetraphylla. The chloroform extract and total chlorophyll content of aerial parts were negatively correlated to the total root alkaloid content in all the species of Rauwolfia. The relationship between these was found to be “Total root alkaloid content= 2.047 – 0.016 x chloroform extract of aerial parts =2.304–1.434 x total chlorophyll content of aerial parts” The relationship can be effectively utilized in the estimation of root alkaloid, in Rauwolfia spp., even at the early stages of growth, without uprooting the plants.ThesisItem Open Access Artifical induction of polyploidy in Cucumis sativus L(Department of Agricultural Botany, College of Agriculture, Vellayani, 1993) Girish Kumar, KG; KAU; Chandramony DAn investigation entitled “Artifical induction of polyploidy in Cucumis sativus L. was carried out as two separate experiments. Experiment I, was (in-vivo study) was carried out at the College of Agriculture, Vellayani during the period September 1991 to February 1991. Experiment II (in-vitro study) was carried out at the Tissue culture laboratory attached to Department of Pomology, College of Horticulture, Vellanikkara during the period January 1991 to july 1991. The main objective of Experiment I was to study the effect of colchicine for inducing polyploidy in seed, seedling and apical bud treatments. Objectives of Experiment II were to standardise a suitable medium for embryo culture and to study the effect of colchine on proembryos, mature embryos and dry seed embryos under in - vitro conditions. Experiment I was laid out in RBD with two replications. Experiment II was carried out in CRD with three replications. The two varieties of Cucumis sativus used for the present study were Seethal and Delila. The abstract of results is given below. Experiment I Survival of plants in both Seethal and Delila was significantly affected by increasing colchicine concentration 0.2 to 0.4 per cent and with increasing period of treatment from two to six hours. Survival was significantly low in apical bud treatment. Maximum survival was noticed in seed treatment of colchicine 0.2 per cent for a period of four hours. At early growth stage significant reduction was noticed in length of vine, number of branches per plant and number of leaves per plant along with the increase in colchicine concentrations, from 0.2 to 0.4 per cent, and period of treatment, from two to six hours. Seed treatment gave maximum value for these parameters in both varieties except number of leaves in Delila. These variations seen during early growth stages were found to be diminishing at later growth stage (60 days growth stage). Delay in both male and female flower opening along with significant reduction in number of male and female flowers was noticed in higher colchicine concentrations and in lower period of treatments. Mode of treatment did not exert any significant influence on number of days taken for flower opening and total number of flowers produced per plant in both varieties except on number of days taken for female flower opening in Seethal in which by apical bud treatment maximum delay was noticed. With increasing colchicine concentration from 0.2 to 0.4 per cent and period of treatment from two to six hours significant increase in stomatal length was noticed in both varieties. Mode of treatment exerted no significant influence on stomatal length. All the fruit characters ie. Number of fruits per plant, length of fruit, girth of fruit and weight of fruit studied, were not significantly influenced by the treatments tried. In both varieties pollen size and sterility increased considerably with increasing colchicine concentration. Apical bud treatment gave significantly high values for pollen size and pollen sterility in Delila. Seed treatment recorded minimum pollen size and pollen sterility. Cytological studies were conducted in the root tips of colchicine treated seeds and metaphase and anaphase stages were obtained in the normal diploid cells. But the enlarged colchicine affected cells showed very poor stainability. Eepeiment II Standardisation of a suitable medium was carried out by using MS medium as the basal medium. MS medium supplemented with 0.1 mg/L of IAA was found suitable for embryo culture. Three types of embrayo viz., pro-embryo, mature embryo and dry seed embryo were used for embryo culturing. Embryogenesis was delayed significantly with increase in colchicine concentration from 0.02 to 0.04 per cent in both varieties. When pro-embryos were used for inoculation significant delay was noticed for embryogenesis in both varieties. Regeneration of calli was reduced significantly with increase in colchicine concentration. Pro-embryos gave lowest and dry seed embryo gave highest regeneration percentage in both varieties. Length of plantlet and number of leaves produced per plantlet in culture tubes were reduced significantly in the higher levels of colchicine concentration. Pro-embryos gave lowest and dry seed embryos gave highest values with respect to these parameters. Plantlets from pro- embryo showed lowest survival under green house conditions in both varieties. Colchicine concentration exerted no significant influence in Seethal. But in Delila with increasing colchicine concentration from 0.02 to 0.04 percent, survival of plants in green house reduced significantly. Day of treatment had no significant influence in all the parameters studied. On the basis of present study it can be concluded that different concentrations of colchicine, different periods of treatment and different modes of colchicine treatment can induce significant changes in the survival of plants, cytomorphological characters of the plants and pollen sterility. With increasing colchicine concentration and period of treatment the variations increased progressively. But considering the lethal effects as reflected on the survival of plants, 0.2 per cent colchicine application for two hours by seed treatment is desirable under in-vivo condition. Under in-vitro condition use of dry seed embroyo is best for embryo culture which can be successfully carried out by using MS medium modified with 0.01 mg/L of IAA. Colchicine 0.02 per cent can be used for the induction of polyploidy under in-vitro conditions. Since it is effective in producing variations with minimum deleterious effects.
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