The maximum average temperature (29.6ºC) was recorded in the month of May and the minimum average temperature (14.6ºC) in January, 2007. However, the 5th May was observed as the hottest day of the year with a temperature of 34.0ºC and 17th January was the coldest one with a temperature of 11.8ºC. The maximum relative humidity 88.2% was observed in July and the minimum 39.6% was recorded in March. The total annual rainfall recorded during 2007 was 3698 mm with 156 rainy days. The maximum rainfall of 718mm and rainy day (26) was recorded in the month of August. The maximum rainfall, recorded
in a single day was 108 mm, on 2nd September 2007.
Daily weather data viz., temperature (maximum and minimum), relative humidity (maximum and minimum), wind direction, rainfall and cloudiness were recorded and the data were sent to Indian Metrological Department, Pune for mathematical model. The weather conditions were predicted for next four days and a copy out put data were sent back to the centre. Based upon the weather forecasted, agriculture operation in and around Kolasib were released as bulletin from the centre to the farmers.
WEATHER
Table 1. Mean monthly weather parameters of ICAR Mizoram Centre, Kolasib, Mizoram for the year 2007
Month Temperature(0C) Relative humidity Total rainfall No of rainy
(mm) days
Min. Max. Min. Max.
January 14.6 21.2 49.8 62.5 - -
February 16.8 23.2 51.5 63.7 80.0 6.0
March 19.5 26.8 39.6 59.0 30.0 3.0
April 21.2 28.2 57.8 71.5 309.5 14.0
May 23.1 29.6 62.3 74.1 403.0 16.0
June 23.2 28.5 68.0 77.0 670.0 19.0
July 22.9 27.4 80.4 88.2 395.5 26.0
August 23.1 28.8 75.5 88.1 718.0 26.0
September 22.7 28.0 79.1 81.8 705.5 23.0
October 21.5 27.2 69.3 81.7 281.5 14.0
November 19.9 25.9 69.6 79.3 105.0 6.0
December 15.3 22.3 59.1 73.0 - -
Total 3698 153
RESEARCH ACHIEVEMENTS
CROP SCIENCE
RICE
Experiments on variety evaluation for upland rice, lowland rice, ragi and maize were conducted but yield data could not be collected due to severe rodent infestation during grain filling stage due to
‘Mautam’ 2007
Effect of integrated nutrient management in upland rice
The maximum plant height (86.11 cm), maximum number of tillers/ sq.m (263.88), maximum number of grains per panicle (82.55) and grain yield of rice(3.07 t/ha) were recorded with integrated management (FYM 10t/ha+ BF + NPK40:30:20 kg/ha), followed by 100% inorganic farming (80:60:40 kg N, P and K/ha) .
Effect of nutrient supply system through organic manures
Application of FYM @15t/ha resulted in maximum plant height (75.66 cm), number of tillers/ sq.m (235.55), number of grains per panicle (83.11) and yield (2.91 t/ha) followed by pig manure@ 10t/ha
Weed management in organic rice cultivation Rice variety IURON -514 was planted and a uniform dose of FYM @ 15t/ha was applied with
spacing of 20X10cm produced maximum plant height (82.33 cm), number of tillers/ sq.m (258.00), number of grains per panicle (102.66) and grain yield point of view (3.33 t/ha), followed by 2 hand weeding (HW) alone and 1 HW + Surface mulching with farm waste.
INSECTS AND PESTS
Rice yellow stem borer, Scirpophage incertulas Walker, Pyraustidae, Lepidoptera
The yellow stem borer is the dominant and the most destructive one. It is a regular pest in almost all districts of Mizoram. The extent of crop loss varies from one to nineteen per cent in early-planted and 25-50 per cent in late planted rice crops.
Striped rice borer, Chilo suppressalis Walk, Crambidae, Lepidoptera
Damage is caused to upland or lowland rice when the crop is at the ‘bunting’ or ‘pregnant’ stage.
The damage is not easy to see as the plants may still remain green in colour. The only sign that a pest is present may be when the ear fails to emerge or if the rice ear does manage to emerge it may not produce full grains; such empty ears may be white in colour.
Rice leaf folders
Three species are present in Mizoram viz., Cnaphalocrocis medinalis, M. patnalis, M. ruralis.
Of these, C. medinalis was identified as the
Stem borer adult White ear symptom
dominant species in Mizoram The damage is caused by the caterpillars which fold the leaf blades into tubular structures and feed on the green leaf tissues within these structures.
Rice earhead bug, Leptocorisa orotorius (Thunb.) and L. acuta, Alydidae, Hemiptera
In Mizoram, 25-40 per cent grains were damaged due to its infestation.
Earhead bug
Rice Thrips, Stenchaetothrips biformis (Bagnall), Thripidae, Thysanoptera
The rice thrips is a sporadic pest of upland and lowland rice infesting mostly young plants. The infestation of thrips was found almost in all districts of Mizoram.
Rice skipper, Pelopidas mathias F., Hesperiidae, Lepidoptera
Skipper is a one of the important pest of rice, with extensive distribution in rice growing regions especially in the upland rice. It is common pest on rice throughout Mizoram.
Rice swarming caterpillar, Spodoptera mauritia Hub., Noctuidae, Lepidoptera
The rice swarming caterpillar S. mauritia is a
sporadic pest which occasionally causes serious loss to rice crops in almost all districts of Mizoram.
Green leafhoppers (GLH), Nephoteltix spp., Cicadellidae, Hemiptera
Nephoteltix virescens was identified as the dominant species in Mizoram. When the epidemic is severe, 100 per cent yield loss can occur.
White backed planthopper, Sogatella furcifera (Horvath), Delphacidae, Hemiptera
The white backed plant hopper (WBPH) has emerged as a major pest of rice in the recent years destroying sizeable proportions of the crop. This occurs in both upland and lowland rice environments.
White grubs, Holotrichia spp., Melolonthidae, Coleoptera
The grub is about one half or an inch in length and may be found in the soil beneath the damage rice plants.
Gall midge, Orseolia oryza (Wood-Mason), Cecidomyiidae, Diptera
The yield loss due to gall midge varies from 3 to 70 per cent.
Rice Whorl Maggot: Hydrellia philippina Ferino, Ephydridae, Diptera
In Mizoram, it caused 5 to 10 per cent yield loss on the first crop during May to September.
The possible reason for the reported yield loss may be due to the inability of the plants to fully recover from the whorl maggot damage.
Other insect pests of rice
Some insects like orange winged hopper, pollen feeding beetles, etc. are predominant pests in rice growing areas of Mizoram.
Orange winged hopper Pollen feeding beetles
Table Varietal screening of insect pests of rice
Name of the insect pests Rice varieties
RCPL-76 RCM-11 RCPL-1-126 RCPL-1-122 RCM-22 RCM-18
Rice stem borer - * - - - -
Rice leaf folder * * * * * *
WBPH * * * * * *
White leafhopper * * * * * *
Thrips - - - - * -
Green leaf hopper - * * * - -
Blue leaf hopper - * - - - -
Grass hopper * * * * * *
Flea beetle - * * * * *
Pollen feeding beetle - * - * - -
Spider * * * * * *
Natural enemies * - - - - -
MAIZE
AGRONOMICAL PRACTICES
Effect of integrated nutrient management practices in maize
The maize crop with a row to row spacing of 50cm and 20 cm plant to plant produced maximum plant height (202 cm), cob length (17.11cm), number of grains per cob (496.66) and the highest grain yield (5.17 t/ha) with FYM 10t/ha+ BF + NPK40:30:20 kg/ha, followed by 100% inorganic management (80:60:40 kg N, P and K/ha).
Effect of organic manures in maize
The maximum values for cob length (11.88), number of grains/cob (363.13) grain yield (37.11 q/ha) were recorded with FYM @15t/ha, followed by pig manure @ 10t/ha (10.77).
Weed management in organic maize cultivation Maize variety RCM 1-1 was planted following a spacing of 50X20 cm and a uniform dose of FYM
@ 15t/ha was applied. The maximum values for cob length (19.00 cm), number of grains/ cob (458.33) and grain yield were recorded with stale seed bed + 2 hand weeding (HW) and 1 HW + surface mulching with farm waste.
INSECTS AND PESTS
Maize stem borer, cob borer and aphids were the major insect pests of maize both in Jhum and terraced fields in Mizoram. Termites were also found in the early crop stage. The incidence of pink borer was very low. Maize stem borer infestation was seen usually a month after sowing. The pest caused windowing and dead hearts. The infestation was noticed till harvest. The caterpillar was yellowish brown with brown head.
Stem borer symptoms
PULSES
Lentil
Varietal evaluation trial on lentil in foot hills Eighteen varieties were tested. The maximum plant height (71.00 cm) was recorded with variety L7-714. Maximum number of branches/ plant (6.2) and the highest seed yield 1.0 t/ha was recorded with variety L7-710.
Varietal evaluation trial on lentil in foot hills Nineteen entries were evaluated. The maximum plant height (68.1 cm) was recorded with variety L7-829. Maximum number of branches/ plant (10.8) with variety L7-802 and highest seed yield (2.9 t/ha) was recorded with variety L7-829
Field pea
Varietal evaluation trial on field pea
Twenty varieties evaluated. The highest grain yield was recorded with variety P7-672 (3.0 t/ha) followed by P7-651(2.5 t/ha).The maximum plant height (109.7 cm) was recorded with variety P7- 663. Maximum number of branches / plant (11.1) was recorded with variety P7-676. Maximum number of pods/ plant (86.00) was recorded with P7-676.
INSECT AND PESTS Red gram
Pod boring weevil, stem borer, pod fly were the major insect pests of red gram. Among these insect pests, pod boring weevil was serious pest on this
crop. Pod boring weevil alone caused 70 to 80 per cent damage to the pods and 40-50 per cent to the grains.
Lentil
Pod borer, leafhoppers and aphids were the major insect pests of lentil in Mizoram.
Leafhoppers and aphids sucked the sap from the plants and caused yield loss up to 10-15 per cent.
Some of the insects like ash weevil, grasshopper, etc were minor insect pests.
Pea
Pod borers, plume moth, pod fly, blue butterflies were recorded as major insect pests of pea in Mizoram.
Green gram/black gram/rice bean
Blister beetle was the most serious pest of green gram and caused yield loss up to 25-30 per cent.
The insect pests of green gram recorded were stem fly, blister beetle, flea beetle, aphids, jassids, leaf folder, green shield bug, leaf footed bug, pod bug, grasshopper and semilooper.
Lab-lab
Blister beetle was the most serious pest and caused yield loss up to 30-40 per cent. The major pests of lab-lab recorded were semilooper, pod borer, leaf folder, blue beetle, pod bug, blister beetle, aphids and pod boring weevil. Some of the minor insect pests were hairy caterpillars and ash weevil.
Cow pea
The major insect pests of cow pea recorded were pod bug, pod boring weevil, blister beetle and hairy caterpillar. Cow bug was considered as minor insect pests.
Adult of pod boring weevil Grub of pod boring weevil
OILSEEDS
AGRONOMICAL PRACTICES
Varietal evaluation trial on confectionary groundnut
Eight varieties were evaluated with spacing of 45 cm X 10 cm. A uniform dose of FYM @ 10t/ha was applied. Maximum pod yield 2.2 t/ha was recorded with variety ICGS-76 followed by M-13 (2.2 t/ha). Maximum plant height (70.9 cm) was recorded with variety ICGV-86590. Maximum number of pods/ plant (22.7) was recorded with variety M-13.
Front line demonstration on groundnut Front line demonstrations were conducted at the research farm in collaboration with the NRCG Junagarh.
INSECTS AND PESTS Mustard
More than 30 insect pests were found to infest the mustard viz., mustard sawfly, cabbage butterflies, flea beetle, pod borer, aphids, pod sucking bug, etc. Mustard aphids are the main pest of mustard causing 25-30 per cent reduction in yield. Cabbage butterflies are the common insect pest causing yield loss to the mustard crop. Mustard sawfly is a serious pest on seedling stage. Flea beetles were found throughout the cropping season.
Groundnut
Groundnut was damaged by a number insect pests of which hairy caterpillar, leaf miner, leaf webber, blister beetle, aphids, white grubs, earwig, termites, were important pests. The leaf miner was very serious pest and it caused yield loss up to 20- 25 per cent. The soil insect like termites, earwig and white grub were major yield limiting factors.
Hairy caterpillar Soybean
In Soybean stem fly, leaf webber/folder, aphids, etc. were the most destructive insect pests. These
folders, voracious feeders caused loss in soybean yield up to 10 per cent during kharif season.
Soybean stem fly on soybean caused 15-20 per cent yield loss.
FRUITS
INSECTS AND PESTS Citrus
In the north eastern hilly region 26 species have been recorded attacking citrus. Insect pests attacking citrus (Khasi mandarin) are citrus leaf miner (P. citrella Stainton), lemon butterfly (Papillio demoleus L.), scale and mealy bug.
Citrus leaf miner, Phyllocnistis citrella (Stainton), Gracillariidae, Lepidoptera
Citrus leaf miner larvae feed by creating shallow tunnels, referred to as serpentine mines, in young leaves. Usually only one leaf mine is present per leaf but heavy infestations may have 2 or 3 mines per leaf; up to 9 mines on large leaves have been found in Mizoram.
Citrus or lemon butterfly, Papilio demolious L., Papilionidae, Lepidoptera
Infestation was more in nursery and young plantations where the seedlings and new flushes were defoliated.
Scale insect, Aonidiella auriantii Maskell, Diaspididae, Hemipetra
More than 50 species of scales have been recorded feeding on citrus. Scales are more prevalent in the temperate conditions. The soft scales the have no separate cover but sometimes a hard skin or a protective waxy secretion.
Citrus scales are of two distinct types-armoured scales, which have hard cover separate from the body providing protection to the body underneath.
Mealy bug, Planoccus citri Risso, Pseudococcidae, Hemiptera
Mealy bugs are another group of insects with serious consequences. Here, the seedlings and
leaves are attacked. Citrus mealy bug, the most common species, has a pinkish body that is visible through the powdery wax. The filaments around its margins are not appreciably longer at the posterior end.
Banana
Banana is the second most important crop in Mizoram. The most important insect pests of banana recorded were leaf and fruit scaring beetle, rhizome weevil, pseudostem weevil, skipper and
aphids. Passion Fruit
The most important insect pests recorded were fruit flies, vine bug, stink bug, leaf beetle, etc. If fruits are punctured when nearly mature, the only effect is an external scar and it cause yield loss up to 10-15 per cent damage to the fruits of the passion fruit.
Fruit fly damage
Papaya
The most important pests recorded were weevil, mite, etc. In the nursery leaf folder was the most important insect pests.
Leaf and fruit beetle (Brown)
Leaf and fruit beetle damage
Leaf and fruit beetle (Black)
Weevil damage
Grub of pseudostem weevil
Pupa of pseudostem weevil
Adult emerging from
coccon Weevil damage
Skipper parasitoid emerging from
skipper pupa
Pupa of banana skipper
Weevil Leaf folder
Guava
Guava was found infested by more than 25 insect pests in Mizoram and among them guava trunk borer, scale, fruit sucking moth and fruit flies were the most serious pests. The trunk borer losses in the guava orchard ranged from 25-75 per cent.
The fruit sucking moths are major yield and quality limiting factor in guava cultivation. Some non- insect pests like rat are also causing damage to the guava fruits. Tea mosquito bug was the major insect pests present almost throughout the period and it caused yield loss up to 15-20 per cent.
Mite Mite damage
Mite damage (webbing)
Mango
Most important and serious pests of mango in Mizoram were stone weevil, scale insect, fruit flies, leaf webber, stem borer, leaf gall, shoot borer, etc.
Some insect pests like shoot borer, leaf webber, leaf twisting weevil were of minor importance.
Litchi
Indigenous varieties are common and grown in the lower altitude of the region. Fruit and stone borer, sucking bug, leaf webber, mite, etc. were the most serious pest of litchi in Mizoram. The fruit and stone borer damage was recorded up to 25 per cent in the litchi orchard.
Trunk borer symptoms Trunk borer grub
Fruit sucking moth and its damage symptom
VEGETABLES
INSECTS AND PESTS Tomato
Insect pests of tomato recorded damaging were fruit borer, thrips, aphids, jassids, leaf miner, etc.
Fruit borer caused yield loss up to 20-25 per cent in Mizoram.
Tomato fruit borer and its damage symptoms
Chilli / Capsicum
The major insect pest recorded aphids, fruit flies, scale, mealy bugs, whitefly, stink bug, flea beetle, etc. Both nymphs and adults can cause severe damage to the crop. Fruit fly was the most important insect pest of chilly in Mizoram.
Bhendi
This crop is grown widely in Jhum as well as terraced lands. Major insect pests of bhendi recorded were fruit borer, shoot borer, flower beetle, jassids, aphids, semilooper, leaf roller, fruit bugs, etc. Blister beetle caused more than 50-100
% loss . Ash weevil and flea beetle were also recorded as major insect of bhendi in Mizoram.
Brinjal
Key pests responsible for qualitative and quantitative losses were fruit and shoot boresr.
Some other insect pests like aphids, jassids, mealy bug, scale, flea beetle, epilachna beetle, etc. were also considered as major insect pests..
Beans
Different types of beans are grown for vegetables in Mizoram. The main pests recorded were aphid, stem fly, flea beetle, blister beetle, epilachna beetle, hopper, etc. Blister beetle was one of the major insect pests.It caused yield loss up to 25-50 per cent.
Cole crops
Insect pests recorded on cole crops were cabbage butterfly, cabbage semilooper, diamond back moth, hairy caterpillar, head borer, aphids, flea beetle, painted bug, sawfly, etc. Cabbage butterfly was the most important insect pests of cole crops.
INTEGRATED NUTRIENT MANAGEMENT IN VEGETABLES
Integrated nutrient management in cabbage Integrated nutrient management (INM) trial was conducted to examine the response of fertilizer and vermicompost either alone or in combination on growth, yield and quality traits of cabbage (Table:
1). Five treatment combinations were
T-1 100 % fertilizer + 0 % vermicompost T-2 75 % fertilizer + 25 % vermicompost T-3 50% fertilizer + 50 % vermicompost T-4 25 % fertilizer + 75 % vermicompost T-5 0 % fertilizer + 100 % vermicompost
• Fertilizer dose @ 100: 60: 60 kg NPK/ ha and Vermicompost dose @ 15 t/ ha
One month old seedlings of cultivar Blue Diamond were transplanted on 07.12.2007 in triplicate. The spacing and bed size was kept at 50 x 50 cm and 4 x 2 m, respectively. Gross plant weight and net head weight were higher in all the treatments as compared to vermicompost alone.
Harvest index was highest in fertilizer only (T-1) but it is at par with T-2, T-3 and T-4 treatment. There was no significant response for any treatments on the number of non-wrapper leaves. Head compactness was directly associated with the long stay in field, shelf life and transportability of head.
Its compactness showed positive association with the amount of vermicompost applied. The study revealed that integration of vermicompost along with fertilizer (T-3 and T-4) enhances the yield potential and quality of head.
Table 1. Response of INM on growth, yield and quality parameters of cabbage
Treatment Gross Net Harvest Leaf Head plant head index number compact-
weight weight (%) ness
(g) (g)
T-1 2207 1608 73.0 12.5 36.0
T-2 2234 1594 71.4 12.1 40.5
T-3 2217 1587 71.6 12.1 43.4
T-4 2187 1448 66.2 12.4 44.2
T-5 1701 1044 61.4 12.1 45.4
Average 2109 1456 68.7 12.2 41.9
(P = 0.05) 77 133 7.6 NS 5.8
Integrated nutrient management in tomato The treatments were same as INM in cabbage.
Data are presented in Table 2.
One month old seedlings of F1 hybrid Avinash- 2 were transplanted following randomized block design in triplicate on 03rd December, 2007. The plant spacing and bed size was kept at 50 x 50 cm and 4 x 2 m, respectively. It was visual that T-5 treatment has less chlorophyll in their leaves. Also fruiting period was shorter as compare to other
treatments showing the high response of hybrid to nitrogenous fertilizer. There was no significant responses of treatments on stem thickness, specific leaf weight and fruit size. Non-significance of fruit size revealed that vermicompost had no effect on cell expansion and or cell division of fruits. Plant height, single leaf area, single leaf fresh weight, fruit number and fruit yield/ plant had significant response as compare to vermicompost alone. Single fruit weight was highest in integrated/ combination treatments only that might be due to high fruit density and TSS. The fruit density, TSS and post harvest life of fruits (fruit quality) increased with increase in vermicompost quantity. Post harvest life of fruit increased by 90-250 % with the application of vermicompost as compare to fertilizer alone, especially in summer tomato. The present study indicated that integration of vermicompost along with fertilizer (T-3 and T-4) enhance the growth of plant, yield potential and quality of fruit. (Table 2).
Evaluation of tomato cultivars during summer season
One month old seedlings of five cultivars were transplanted on 12th January, 2007 in triplicate. The spacing and bed size was kept at 50 x 50 cm and 4 x 2 m, respectively. The number of fruits/ plant was recorded highest in Avinash-2 which is at par with Swaraksha but total yield/ plant was highest in Avinash-2 because of larger fruit size. Swaraksha is highly susceptible to blossom end rot due to calcium deficiency and it is more visually conspicuous with increase in temperature. (Table 3).
Table 3. Performance of tomato cultivars during summer season
Cultivar No. of Single Fruit Disease reaction fruits/ fruit yield/
plant weight plant (g) (g)
Sel-3 16.4 45.1 738 -
Shivam 18.7 40.5 757 -
No-3560 25.5 33.3 853 Susceptible to bacterial wilt during September- October transplanting only.
Swaraksha 28.5 54.2 1540 Susceptible to blossom end rot
Avinash-2 32.1 64.9 2088 -
Avg 24.2 47.6 1195 -
(P = 0.05) 4.1 4.2 308 -
Mulching in tomato
The average annual rainfall of Mizoram is around 351 cm but main vegetable growing season (October-April) receives only 11.4 % of total (2007-08). Due to this, winter season vegetables face the problem of water scarcity. Keeping this Table: 2 Response of INM on growth, yield and quality of tomato
Treatment Plant Stem Single Single Specific Fruit Single Fruit Fruit Fruit TSS Post height thickness leaf leaf leaf number/ fruit yield/ size density (Brix) harvest (cm) (mm) area fresh weight plant weight plant (cm2) (g/ m3) life
(cm2) weight (g/ cm2) (g) (kg) (day)
(g)
T-1 87.7 14.1 30.6 902.3 30.0 33.7 79.2 2.658 26.4 0.792 4.3 6.3
T-2 85.6 14.3 34.1 935.7 27.5 33.1 85.4 2.839 30.6 0.894 4.3 12.0
T-3 90.3 14.7 32.9 905.0 27.7 32.8 88.9 2.939 31.0 0.907 4.5 13.7
T-4 96.4 13.6 34.2 915.7 26.8 27.3 82.6 2.266 28.6 0.908 5.2 14.0
T-5 80.5 13.8 24.8 664.3 26.7 21.0 77.3 1.628 27.8 0.971 5.1 16.0
Avg. 88.1 14.1 31.32 864.6 27.74 29.58 82.68 2.466 28.88 0.8944 4.68 12.4
(P = 0.05) 5.7 NS 5.0 113.3 NS 6.2 4.8 0.605 NS 0.038 0.6 2.1
Blossom end rot