• Nutritional requirements of seed production plots depends on soil, specific variety and parental materials chosen for seed production.
• Nutritional levels recommended for different plant types and management practices to be followed for realising higher yields and returns per unit of nutrient applies are as follows :

• In case of basal application, drill the fertilizer just by the side of seed row and below the seed.
• Wherever top dressing is given additional dose of nitrogen may be applied in the form of split application atleast 6 cm away from the plant.

• Follow the recommended tillage and seed bed preparation to minimise problems of weed control during first 45 days of crop growth.
• Wherever conditions warrant, use chemical weedicides like Fluchloraline or Trifluraline (a) 1 kg ai/hac, 3-5 days prior to seeding.
• If necessary, resort to manual weeding within 20-25 days after sowing followed by interculture with bullock drawn blade harrow for checking weed growth effectively.
• When the crop is 35-45 days old, open 45-60 cm wide and 30-45 an deep furrows in between the rows by running broad band iron plough.
• Such practice not only provides earthing up to the young plants but also facilitates easy irrigation through furrows with minimal or no direct contact of above ground portion of plants with water.

• The number and intensity of irrigations depend on specific soils, their water holding capacity and the crop season in question.
• As compared to heavy soils, light textured soils require more frequent irrigations.
• For kharif crop which benefits from South west monsoon 4-6 irrigations may be more than sufficient.
• During rabi the number of irrigations may go up to 6-8 while in summer as many as 15-20 irrigations are required at intervals of 7-10 days.
• Proper timing of irrigation is very important to avoid moisture stress at sensitive crop growth stages viz. primordial initiation in various sequential order branches
.
• Hence schedule irrigations accordingly
• Prevalence of moisture stress at the above stage may lead to production of more male flowers in monoecious varieties.

• Unless checked throughly by timely contol measures, insect pests and diseases can cause serious qualitative and quantitative losses at any stage of seed production.
• Hence care should be taken at proper time for pest and disease control.

• For ensuring high standards of genetic purity of various varieties, hybrids and their parental material a minimum of 3-4 field inspections are necessary.
• Important parameters/diagnostic characteristics which form the basis for field inspection at different stages of crop growth are described below

• As per the existing standards the maximum permissible limits of off-types in different categories of seed production plots during various field inspections are as follows:

• Monoecists to be retained for pollen source in conventional method of foundation seed production.

** In refined method pollen source from monoecists is eliminated. About 25 to 55% female plants produce interspersed late male flowers in summer and kharif seasons which serve as pollen source.

• Since it is a newly developed method not yet included in the currently followed purification standards. The method is advocated in view of its distinct merit over the conventional method.

1.  Roguing And Field Inspection
2.  Roguing at various crop growth stages
3.  Varieties and male parents of hybrids

• For all varieties and male parents two rounds of roguing are required.
• First about 10 days prior to flowering and the second one coinciding with flowering.
• During preliminary roguing operations look for deviants if any for various diagnostic morphological characteristics like stem colour, internode type, shape of leaves and remove them.
• Immediately after primary spike initiation, examine the seed production plots for number of nodes up to primary raceme, type of internode, expression of sex, proportion of male to female flowers in the spike, branching and other spike characteristics in relation to the parameters specified for the variety and parental line and pull out all undesirable plants not confirming to the stipulated standards.
• Any laxity in roguing operations or delay in the timing of roguing would have adverse effect on the ultimate quality of the seed and hence follow the schedule strictly.
• Since the flower initiation extends over a period of 10-15 days.
• Carryout second round of roguing for three to five rounds at intervals of two to three days to avoid any possible left overs.

• The diagnostic features of varieties ,Hybrids and their parental material which make their identification early and facilitates roughing of deviant plants.

• The seed multiplication chain in castor comprises of four stages: Nucleus, breeders, foundation, and certified.

• Selfed seed of individual plants of the genotype from selected progenies in nucleus seed production plot.

• Selfed bulk seed of selected progenies raised from basic seed stocks for continuation of seed production/ multiplication chain.

• Second phase in seed multiplication chain, which is carried under strict supervision of original or sponsoring breeder.
• The starting material for breeder seed comes from the selfed bulk of selected progenies.
• Further selection helps minimize variation for environmentally sensitive characters namely sex expression and node number up to primary raceme.

• This is the third phase in seed multiplication which is carried out by recognized seed producing agencies in public and private sector under the strict supervisors of seed certification agency of the state concerned.

• The final phase in the seed multiplication chain produced by registered seed growers under the supervision of seed certification agency of the state concerned.

• Seed that is not meant for further seed production.

• Seed harvested from female parent in hybrid seed production plot.

• Standard varieties and male parents of commercial hybrids.

• About 50-100 selected and selfed progenies of preceding crop season constitute the source seed for maintenance and initial multiplication of basic seed stocks.

• Plant selfed seed if 200-500 selected plants in progeny rows ensure that a minimum of 20-25 plants are there in each progeny row.

• At primary spike initiation inspect the field and select about 100-200 uniform looking progenies confirming to the mean node number, sex expression and all other will defined morphological characteristics of the genotype.
• In each selected progress label 5-10 representative plants, which have same node number up to primary spike and confirm to the mean specified for the genotype.
• From each labelled plant of the selected progenies self around 3-5 spike per plant other than primary spikes.
• At maturity record detailed observations on the unselfed primary spike on various yield components such as total and effective spike length (primary), number of productive capsules per spike.
• Harvest the individual primary spikes (unselfed) plant and progeny wise and record yield per spike, 100 seed weight, percent seed oil content after threshing and drying the seed to a constant moisture.
• Bulk the harvest from various order selfed spikes in each plant and progeny.
• Select about 50-100 progenies based on Various characters of primary spike (unselfed) i.e. yield, 100 seed weight, seed oil content, length of spike, number of productive capsules per spike.
• Draw about 50 seeds from each labeled plant in 50-100 selected progenies for us as seed source for further maintenance and bulk the remaining portion of selfed seed from all selected progenies for recycling in to the breeder seed production.
• Under conditions of good management, one could easily obtain about 10 kg selfed seed (nuclear) from 50 selected progenies of 10 plants each (500 plants) which will be sufficient to cover about one hactare of breeder seed production.

• Use selfed seed of individual plants obtained from higher order spikes i.e. sixth and above sequential order branches in the preceding crop season.

• The best season for taking up female seed production plots is either summer or kharif, when the day temperatures are above 32⁰.
• Plantings may be done either in January or February.
• Seed obtained from 100-150 selected progenies may be dibbled at a spacing of 90 cm between row and 60 cm within the row.
• Ensure a minimum of 20-25 plants for every progeny row.

• At primary spike initiation exert preliminary selection pressure and chose 50-75 individual plant progenies based on the uniformity for various morphological characters.
• Especially node number up to primary raceme and femaleness.
• Within each selected progeny retain about 10-15 plants possessing desired node number up to primary raceme, and remove of all monoecists and application of stringent selection for femaleness, there would be less fruit set in the primary raceme.
• After all or most of the first developed female flowers fail to set fruits and drop off the primary as well as subsequent order racemes produce interspersed male and bi sexual flowers which serves as a good pollen source to late formed female flowers.
• As a result there will be a progressive increase in the fruit set from secondary to tertiary order and above.
• Inspect carefully each of the selected plants in 50-75 progenies regularly and look for any plants reverting to monoecism in different sequential orders i.e. tertiary, quaternary, pentenary etc.
• In case any plants show reversion to monoecism earlier than sixth sequential order racemes remove and destroy the biproductive parts.

• About 30-50 percent pistillate plants which continue to be pistillate up to fifth sequential order raceme start reversion monoecism after 6-6 ½ months of planting.
• At this stage, self about 5-6 racemes of sixth end higher sequential orders in every plant irrespective of whether they revert to monoecism or not.
• Harvest and thresh the seed of all open pollinated racemes plantwise and retain them with proper labeling until the stability of pistillateness/femaleness up to fifth sequential order racemes is confirmed.
• Delete all such open pollinated seed of the plants which revert to monoecism in any of the secondary to pentenary order racemes and retain the rest.

• At the end of the crop cycle which roughly takes 8-9 months from planting under irrigated conditions harvest plantwise selfed seed and number the progenies.
• Record 100 seed weight, oil content and other characters on the seed harvested from open pollinated racemes of all selfed and finally selected plants.
• Estimate progeny means for each of the above attributes and compare them with the corresponding standard values for the female parent.
• Any progeny which deviates significantly from normal should be deleted.
• Bulk the seed harvested from open pollinated racemes of all selfed and selected plants.
• This forms the source for breeders seed production.
• The remaining seed harvested from selfed racemes of individual, plants is used for further maintenance and initial multiplication of basic seed stocks.

• Plant bearing racemes which have female/pistillate and male flowers on upper and lower parts respectively.

• Population containing variable proportion of stable pistillate, sex reversals, pistillate with environmentally sensitive staminate flowers and monoecious plants.

• Monoecious inbred line used as pollen parent in hybrid seed production.

• Plants which are females to start with and revert to monoecism later in one or more sequential order branches.
• If a female plant reverts to monoecism in secondary or tertiary order it is an early revertant.
• If reversion takes place in quaternary or beyond it is late reversion.

• Interspersed staminate flowers which develop all along the length of female raceme usually after the failure of first developed female flowers to set fruits.
• The intensity of interspersed staminate flowers is more conspicuous in male promoting environment.

• Both pistil and stamens are present in the same flower.
• Only under certain environmental conditions the female parent (VP-1) produces 2-5 bisexual flowers per spike.

• Besides the routine two rounds of roguing for removal of off types based on morphological (stem, colour, internode type, leaf shape, bloom, nodes up to primary raceme, sex expression, branching etc) the seed produce has to inspect every female plant regularly for any possible reversion to monoecism at secondary, tertiary and quarternary orders.
• In case of breeder and foundation seed production plots plants which revert to monoecism early in secondary, tertiary and quaternary order branches have to be removed and destroyed.
• As regards hybrid seed production plots, it is not necessary to remove whole plant if the reversion to monoecism occurs after tertiary and higher orders.
• Instead all out the specific spike well before anthesis and either destroy or throw them beyond the permissible isolation distance otherwise it may serve as pollen source to other pistillate racemes and result in reduced percent of hybrid in certified seed production plots.
• Hence follow roguing operation without any laxity whatsoever.

• For good growth, castor requires fine seed bed with loose sub soil upto 45 cm depth.
• In fields selected for castor seed production, give deep summer ploughing in order to break the hard sub soil facilitate easy root penetration and achieve effective weed control.
• For obtaining required tilth plough the land once again as soon as pre monsoon showers are received followed by 2-3 harrowings using either blade or tyned harrow.

• Time of planting and specific season has profound influence on sex expression.
• While summer and kharif seasons provide ideal male promoting environment for undertaking seed production of varieties male and female parents of hybrids, rabi/winter is the most ideal season for taking up hybrid/certified seed production as it is most conducive for production of female flowers.
• In case of varieties and male parents such an exposure to male promoting environment i.e kharif and summer encourages good expression of less productive plants bearing mostly male spikes which could be easily eliminated through timely roguing.
• Similarly, the female parents when raised in male promoting environments produce environmentally sensitive staminate flowers which are very essential for self reproduction of the female parents.
• Based on the differential genotypic response to environment, the following seeding dates are suggested for various categories of seed.

• The spacing and seed rates recommended for seed production plots of varieties and parental lines of hybrids are as under

• Castor is highly cross pollinated crop.
• The extent of cross pollination mainly depends on the direction and velocity of wind which is the primary source of pollen dispersal.
• The proportion of female and male flowers on the raceme also determines the extent of cross pollination.
• For eg. In monoecious varieties which produce abundant pollen, cross pollination is very much limited even when contamination source is nearer because of the failure of foreign pollen to complete with native pollen.
• On the other hand, genotypes which produce mostly female or 100% female racemes easily get contaminated by foreign pollen from sources located as far as 1000 in distance.
• Besides wind, insects, like honey bees, butter flies, moths etc also play a role in pollen disposal and result in variable levels of out crossing leading to contamination of varieties and parental lines and hence can be a potential source of contamination of improved varieties and parental lines where ever lines not conforming to genetic purity standards are grown with in one kilometer sphere.

• Crop rotation plays a very important role in the production of healthy and superior quality seed.
• Continuous cropping of castor year after year in the same field not only aggravates problems of soil born pathogens and other fungi and also lead to nutritional in balances and decline in yields and returns.
• Added to adverse effect of continuous cropping on yields, there is also the danger of volunteer plants from mature capsules/seed fallen to ground during harvesting operations of previous crop if the field is not rotated.
• Hence take care to see that the field selected for seed production was not put to castor cultivation at least in the preceding two seasons.

• Castor seed production can be successfully taken up on any type of soil provided they are fairly deep, fertile and well drained.
• In general all castor genotypes more particularly the female lines cannot tolerate alkalinity/salinity hence avoid such problematic soils.
• Medium to deep sandy loams and heavy loams are ideally suited for seed production.
• What is more important is the availability of assured irrigation source throughout crop growth period more particularly critical phase of crop growth viz. primordial initiation and flowering in different sequential order branches.

• As far as possible avoid seed production in areas and situations which overlap with that of commercial castor; if unavoidable, choose fields which satisfy the recommended isolation requirements.
• Before embarking on castor seed production in non-traditional areas and situations, ascertain its feasibility and economic viability in relation to prevailing crops and cropping systems in the area.
• Ensure that no perennial castor which grow either wild or raised in waste lands, back yards and along field bunds, irrigation channels, road sides etc are there within the stipulated isolation limits to avoid contamination of seed production plots.
• Avoid problematic soils (saline, alkaline and those which are ill-drained).
• Refrain from continuous cropping of castor in the same fields year after year as such a practice not only leads to higher cost of production but reduces ultimate yields and returns.

• The time and stage of roguing and the diagnostic characteristics which are important at different stages of roguing are listed below