Advances in Hybrid Seed Production of Cotton Crop

UPDATED ON:- 01-01-2024

Advances in Hybrid Seed Production of Cotton Crop:-

परिचय (Introduction):-
·         कपास एक रेशा उत्पादक फसल है। इसे रेशा फसलों की रानी’ भी कहते हैं।
(Cotton is a fiber yielding crop. It is also called as 'queen of fiber crops'.)
·         कपास एक मुक्त परागित फसल है जिसमें 60% परपरागण और 40% स्वपरागण होता है।
(Cotton is an open pollinated crop with 60% cross-pollination and 40% self-pollination.)
·         कपास में पुष्प एकल रूप से पत्तियों के कक्ष से विकसित होते  हैं।
(Flowers in cotton develop individually from the axis of leaves.)
संकर बीज उत्पादन (Hybrid Seed Production):- कपास में संकर बीज का उत्पादन 2 विधियों से किया जाता है -
(Hybrid seed is produced in cotton by 2 methods -)
A. परम्परागत विधि (Conventional method)
B. अपरम्परागत विधि (Non-conventional method)
A. परम्परागत विधि (Conventional method):-
·         यह बहुत अधिक सामान्य विधि है। कपास में विकसित किए गए अधिकांश संकरों का बीज उत्पादन इसी विधि से विकसित किया गया है।
(This is the most common method. Seed production of most of the hybrids developed in cotton has been done by this method.)
·         इस विधि में हस्त विपुंसन  हस्त परागण किया जाता है जो इस विधि के मुख्य गुण हैं।
(In this method, hand emasculation and hand pollination are done which are the main features of this method.)
·         रोपण अनुपात (Planting ratio):- नर  मादा जनक पौधों की पंक्तियों को क्रमश: 1 : 4 के अनुपात में उगाया जाता है। अर्थात खेत के 4/5 भाग में मादा जनक पौधों की पंक्तियाँ उगाते हैं और शेष 1/5 भाग में नर जनक पौधों की पंक्तियाँ उगाते है।नर  मादा जनक पौधों की पंक्तियों के मध्य 5 मीटर की दूरी रखी जाती है।
(Rows of male and female parent plants are grown in the ratio of 1: 4 respectively. That is, rows of female parent plants are grown in 4/5 part of the field and the rows of male parent plants are grown in the remaining 1/5 part of the field. A distance of 5 m is placed between the rows of male and female parent plants.)
·         पृथक्करण (Isolation):- अन्य खेतों से 30 मीटर की पृथक्करण दूरी रखी जाती है।
(An isolation distance of 30 meters is maintained from other farms.)
·         क्रॉसिंग तकनीक (Crossing Technique):- इसमें कुल 9 बिन्दु होते हैं जो इस प्रकार हैं –
(There are total 9 points in this technique which are as follows -)
i. रोगिंग (Roguing):- क्रॉसिंग प्रोग्राम को शुरू करने से पहले नर  मादा जनक पंक्तियों में से सभी ऑफ प्रकार पौधों को हटा देना चाहिए।
(All off-type plants should be removed from the male and female parent rows before starting the crossing program.)
ii. समय (Timing):- विपुंसन दोपहर बाद 2 से 6 बजे के मध्य किया जाना चाहिए तथा परागण अगले दिन सुबह 8 से 12 बजे के मध्य किया जाना चाहिए।
(The emasculation should be done between 2 to 6 o'clock in the afternoon and pollination should be done on the next day between 8 to 12 o'clock in the morning.)
iii. कलिका चयन  विपुंसन (Bud selection and emasculation):- ऐसी पुष्प कलिका का चुनाव करते हैं जो अगले दिन सुबह खुलने वाली होती है। अब इसके बाह्यदलोंदलों  एकसंघी पुंकेसरों को इस प्रकार हटाते हैं कि इसके वर्तिकाग्र  वर्तिका को क्षति  पहुंचे। इस प्रकार विपुंसन हो जाता है।
(Choose such a flower bud that opens in the morning the next day. Now, remove its sepals, petals and monadelphous stamens in such a way that it does not harm its stigma and style. Thus the emasculation is done.)
iv. थैली लगाना  परागण (Bagging and Pollination):- विपुंसित पुष्प कलिका को तुरन्त बटर पेपर थैली से ढक देते है। अगले दिन सुबह परागण करते हैं। क्योंकि हम पृथक्करण दूरी का उपयोग कर रहे हैं इसलिए विपुंसित पुष्प को बटर पेपर थैली से ढकना अनिवार्य नहीं है।
(The emasculated floral bud is immediately covered with a butter paper bag. Pollination is done in the next day morning. Because we are using an isolation distance, it is not mandatory to cover the emasculated flower with a butter paper bag.)
v. पहले 7 सप्ताहों में उत्पन्न होने वाली सभी पुष्प कलिकाओं का विपुंसन  परागण करते हैं ताकि अधिक संकर बीज उत्पादन को सुनिश्चित किया जा सके।
(All the floral buds produced in the first 7 weeks are emasculated and pollinated to ensure more hybrid seed production.)
vi. अगले दिन सुबह निषेचन से पहले सभी अविपुंसित पुष्प कलिकाओं को हटा देते हैं।
(The next day morning, remove all the un - emasculated floral buds before fertilization.)
vii. प्रत्येक परागण के पश्चात पुष्प कलिका के वृन्त के साथ एक टैग बांध देते हैं।
(After each pollination, tie a tag to the pedicel of the floral bud.)
viii. 11वें सप्ताह के पश्चात क्रॉसिंग प्रोग्राम को रोक देना चाहिए तथा नई बनने वाली सभी कलिकाओं  पुष्पों को हटा देना चाहिए ताकि क्रॉसित कलिकाओं का अच्छा विकास हो सके।
(After the 11th week the crossing program should be stopped and all newly formed buds and flowers should be removed so that the crossed buds can grow well.)
ix. Nipping:- शीर्षस्थ प्ररोह को काटकर हटा देते हैं ताकि पौधे की लंबाई में वृद्धि रुक सके और क्रॉसित कलिकाओं को पोषण मिल सके।
(The top shoots are cut and removed to stop the growth in the length of the plant and crossed buds can be nourished.)
·         बॉल का एकत्रण (Collection of bolls):- परिपक्वता पर पूर्ण रूप से परिपक्व  खुली हुई बॉल को उनके वृन्त  टैग सहित तोड़ लेते हैं और एक बास्केट में एकत्रित कर लेते हैं।
(At maturity, pick the fully matured and opened balls with their pedicels and tags and collect it in a basket.)
·         बॉल की छंटाई (Sorting of bolls):- बॉल का फिर से निरीक्षण करके इनकी छंटाई की जाती है ताकि क्रोसित बॉल को सुनिश्चित किया जा सके।
(The balls are re-inspected and sorted to ensure that balls are crossed.)
·         शुष्कन  भंडारण (Sun drying and Storing):- 1 या 2 दिनों के लिए धूप में सुखा लेते हैं और थैलों में भरकर तब तक भंडारित करके रखते हैं जब तक कि संसाधन इकाई तक नहीं पहुंचाया जाता है।
(Dry in the sun light for 1 or 2 days and store them in bags until they delivered to the processing unit.)
·         बोल्स को तोड़ते समयभंडारण  उसके पश्चात भौतिक मिश्रण से हर संभव बचाव करना चाहिए।
(While picking the bolls, storage and subsequent, every possible protection from physical mixing should be done.)
·         Grow out test:- परम्परागत विधि से उत्पादित कपास के संकर बीज का GOT किया जाता है ताकि आनुवांशिक शुद्धता को सुनिश्चित किया जा सके।
(GOT of hybrid seeds of cotton produced by conventional method is done to ensure genetic purity.)
B. अपरम्परागत विधि (Non-conventional method):- इस विधि में विपुंसन करने की आवश्यकता नहीं होती है। परन्तु परागण हाथ से कराना पड़ता है। इस विधि में 2 प्रकार के तन्त्रों का उपयोग किया जाता है –
(This method does not require emasculation. But pollination has to be done by hand manually. In this method, 2 types of systems are used -)
1. तीन वंशक्रम तंत्र (Three Line System)
2. दो वंशक्रम तंत्र (Two Line System)
1. तीन वंशक्रम तंत्र (Three Line System):-
·  इसमें CGMS का उपयोग किया जाता है।
(CGMS is used in this system.)
·   इसमें 3 प्रकार के वंशक्रमों का उपयोग किया जाता है-
(It uses 3 types of lines-)
i. A – line (नर बंध्य वंशक्रम)
[Male sterile line]

ii. B – line (अनुरक्षक वंशक्रम)

[Maintainer line]

iii. R – line (पुन: स्थापक वंशक्रम)

[Restorer line]

·   इस विधि में संकर बीज उत्पादन के 2 मुख्य चरण हैं –

(There are 2 main steps of hybrid seed production in this method -)

a. जनक वंशक्रमों का अनुरक्षण (Maintenance of Parental Lines)

b. वाणिज्यिक संकर बीज उत्पादन (Commercial Hybrid Seed Production)

a. जनक वंशक्रमों का अनुरक्षण(Maintenance of Parental Lines):- 

इसमें जनक वंशक्रमों का आधार बीज उत्पादन किया जाता है।

(In this, the foundation seed production of parental lines is done.)

i. A – line का अनुरक्षण (Maintenance of A - line):-

Ø  इसके लिए A – line का क्रॉस B – line से कराया जाता है।

(For this, the cross of A-line is done with B-line.)

Ø  रोपण अनुपात (Planting ratio):- नर  मादा जनक पौधों की पंक्तियों को क्रमश: 1 : 4 के अनुपात में उगाया जाता है। अर्थात खेत के 4/5 भाग में मादा जनक पौधों की पंक्तियाँ उगाते हैं और शेष 1/5 भाग में नर जनक पौधों की पंक्तियाँ उगाते है।नर  मादा जनक पौधों की पंक्तियों के मध्य 5 मीटर की दूरी राखी जाती है।

(Rows of male and female parent plants are grown in the ratio of 1: 4 respectively. That is, rows of female parent plants are grown in 4/5 part of the field and the rows of male parent plants are grown in the remaining 1/5 part of the field. A distance of 5 m is placed between the rows of male and female parent plants.)

Ø  पृथक्करण (Isolation):- अन्य खेतों से 30 मीटर की पृथक्करण दूरी रखी जाती है।

(An isolation distance of 30 meters is maintained from other farms.)

Ø  दोनों A  B – lines समजीनी होती हैं

(Both A and B - lines are isogenic.)

Ø  बॉल का एकत्रण (Collection of bolls):- परिपक्वता पर पूर्ण रूप से परिपक्व  खुली हुई बॉल को उनके वृन्त  टैग सहित – line पौधों से तोड़ लेते हैं और एक बास्केट में एकत्रित कर लेते हैं।

(At maturity, fully matured and opened balls are picked from A-line plants with their pedicels and tags and collected in a basket.)

ii. B – line का अनुरक्षण (Maintenance of B - line):- 

Ø  इसका अनुरक्षण सामान्य किस्म के समान पृथककृत खेत में उगाकर किया जाता है। पृथक्करण दूरी 30 मीटर   रखी जाती है। 

(It is maintained as a normal variety by growing in an isolated field. The isolation distance is kept 30 meters.)

Ø  बॉल का एकत्रण (Collection of bolls):- परिपक्वता पर पूर्ण रूप से परिपक्व  खुली हुई बॉल को तोड़ लेते हैं और एक बास्केट में एकत्रित कर लेते हैं।

(At maturity, pick the fully matured and opened balls and collect it in a basket.)

iii. R – line का अनुरक्षण (Maintenance of R - line):- 

Ø  इसका अनुरक्षण भी सामान्य किस्म के समान पृथककृत खेत में उगाकर किया जाता है। पृथक्करण दूरी 30   मीटर रखी जाती है। 

(It is also maintained as a normal variety by growing in an isolated field. The isolation distance is kept 30 meters.)

Ø  बॉल का एकत्रण (Collection of bolls):- परिपक्वता पर पूर्ण रूप से परिपक्व  खुली हुई बॉल को तोड़ लेते हैं और एक बास्केट में एकत्रित कर लेते हैं।

(At maturity, pick the fully matured and opened balls and collect it in a basket.)

b. वाणिज्यिक संकर बीज उत्पादन (Commercial Hybrid Seed Production):- 

इसमें संकर प्रमाणीकृत बीज का उत्पादन किया जाता है।

(Hybrid certified seeds are produced in this step.)

Ø  इसके लिए A – line का क्रॉस R – line से कराया जाता है।

(For this, the cross of A-line is done with R-line.)

Ø  रोपण अनुपात (Planting ratio):- नर  मादा जनक पौधों की पंक्तियों को क्रमश: 1 : 4 के अनुपात में उगाया जाता है। अर्थात खेत के 4/5 भाग में मादा जनक पौधों की पंक्तियाँ उगाते हैं और शेष 1/5 भाग में नर जनक पौधों की पंक्तियाँ उगाते है।नर  मादा जनक पौधों की पंक्तियों के मध्य 5 मीटर की दूरी राखी जाती है।

(Rows of male and female parent plants are grown in the ratio of 1: 4 respectively. That is, rows of female parent plants are grown in 4/5 part of the field and the rows of male parent plants are grown in the remaining 1/5 part of the field. A distance of 5 m is placed between the rows of male and female parent plants.)

Ø  पृथक्करण (Isolation):- अन्य खेतों से 30 मीटर की पृथक्करण दूरी रखी जाती है।

(An isolation distance of 30 meters is maintained from other farms.)

Ø  संकर बीज एकत्रण (Hybrid Seed Collection):- परिपक्वता पर पूर्ण रूप से परिपक्व  खुली हुई बॉल को उनके वृन्त  टैग सहित – line पौधों से तोड़ लेते हैं और एक बास्केट में एकत्रित कर लेते हैं।

(At maturity, fully matured and opened balls are picked from A-line plants with their pedicels and tags and collected in a basket.)

·  तीन वंशक्रम तंत्र की कमियाँ (Limitations of three line system):-

i. पुन:स्थापक वंशक्रम बहुत कम उपलब्ध होते हैं।

(Restorer lines are available rarely.)

ii. नर बंध्य कोशिकाद्रव्य के साथ अवांछित लक्षण भी स्थानांतरित होते हैं।

(Undesired traits may also transfer with the male sterile cytoplasm.)

2. दो वंशक्रम तंत्र (Two Line System):- 

·  इसमें GMS का उपयोग किया जाता है।

(GMS is used in this system.)

·   इस विधि के उपयोग से उपरोक्त दोनों समस्याओं का निवारण हो सकता है।

(Both of the above problems can be solved by the use of this method.)

·   इस विधि में संकर बीज उत्पादन के 2 मुख्य चरण हैं –

(There are 2 main steps of hybrid seed production in this method -)

a. जनक वंशक्रमों का अनुरक्षण (Maintenance of Parental Lines)

b. वाणिज्यिक संकर बीज उत्पादन (Commercial Hybrid Seed Production)

a. जनक वंशक्रमों का अनुरक्षण (Maintenance of Parental Lines):-

Ø  अनुरक्षण के लिए नर बंध्य पौधों का विषमयुग्मजी नर उर्वर पौधों से क्रॉस कराते हैं। इसके फलस्वरूप प्रत्येक पीढ़ी में 50 प्रतिशत नर बंध्य पौधे प्राप्त होते हैं।

(For maintenance, the cross of male sterile plants is made with heterozygous male fertile plants. As a result, 50 percent male sterile plants are obtained in each generation.)

Ø  यह इस विधि की मुख्य कमी है कि अनुरक्षण में केवल 50% पौधे ही नर बंध्य प्राप्त होते हैं। केवल इन्हीं 50% पौधों को हम मादा जनक के रूप में उपयोग कर सकते हैं। इससे संकर बीज उपज घट जाती है।

(This is the main drawback of this method that only 50% of the plants are male sterile in maintenance. Only these 50% plants can be used as female parent. This reduces hybrid seed yield.)

Ø  इस समस्या से बचने के लिए प्रति डिबल 2 या 3 बीज उगाते हैं। पुष्पन पर नर उर्वर पौधों को हटा देते हैं। इससे काफी नर बंध्य पौधे बचते हैं जिससे संकर बीज उपज बढ़ जाती है।

(To overcome this problem, grow 2 or 3 seeds per dibble. On flowering, remove male fertile plants. This left a lot of male sterile plants, thereby increasing the hybrid seed yield.)

Ø  रोपण अनुपात (Planting ratio):- नर  मादा जनक पौधों की पंक्तियों को क्रमश: 1 : 4 के अनुपात में उगाया जाता है। अर्थात खेत के 4/5 भाग में मादा जनक पौधों की पंक्तियाँ उगाते हैं और शेष 1/5 भाग में नर जनक पौधों की पंक्तियाँ उगाते है।नर  मादा जनक पौधों की पंक्तियों के मध्य 5 मीटर की दूरी राखी जाती है।

(Rows of male and female parent plants are grown in the ratio of 1: 4 respectively. That is, rows of female parent plants are grown in 4/5 part of the field and the rows of male parent plants are grown in the remaining 1/5 part of the field. A distance of 5 m is placed between the rows of male and female parent plants.)

Ø  पृथक्करण (Isolation):- अन्य खेतों से 30 मीटर की पृथक्करण दूरी रखी जाती है।

(An isolation distance of 30 meters is maintained from other farms.)

Ø बीज एकत्रण ( Seed Collection):- परिपक्वता पर पूर्ण रूप से परिपक्व  खुली हुई बॉल को नरबंध्य पौधों से   तोड़ लेते हैं और एक बास्केट में एकत्रित कर लेते हैं।

(At maturity, they pick fully matured and opened balls from the male sterile plants and collect them in a basket.)

b. वाणिज्यिक संकर बीज उत्पादन (Commercial Hybrid Seed Production):-

Ø  इसके लिए नर बंध्य वंशक्रम का क्रॉस समयुग्मजी नर उर्वर वंशक्रम से कराया जाता है।

(For this, the cross of male sterile line is made with the homozygous male fertile line.)

Ø  रोपण अनुपात (Planting ratio):- नर  मादा जनक पौधों की पंक्तियों को क्रमश: 1 : 4 के अनुपात में उगाया जाता है। अर्थात खेत के 4/5 भाग में मादा जनक पौधों की पंक्तियाँ उगाते हैं और शेष 1/5 भाग में नर जनक पौधों की पंक्तियाँ उगाते है।नर  मादा जनक पौधों की पंक्तियों के मध्य 5 मीटर की दूरी राखी जाती है।

(Rows of male and female parent plants are grown in the ratio of 1: 4 respectively. That is, rows of female parent plants are grown in 4/5 part of the field and the rows of male parent plants are grown in the remaining 1/5 part of the field. A distance of 5 m is placed between the rows of male and female parent plants.)

Ø  पृथक्करण (Isolation):- अन्य खेतों से 30 मीटर की पृथक्करण दूरी रखी जाती है।

(An isolation distance of 30 meters is maintained from other farms.)

Ø  संकर बीज एकत्रण (Hybrid Seed Collection):- परिपक्वता पर पूर्ण रूप से परिपक्व  खुली हुई बॉल को उनके वृन्त  टैग सहित नरबंध्य पौधों से तोड़ लेते हैं और एक बास्केट में एकत्रित कर लेते हैं।

(At maturity, pick the fully matured and opened balls with their pedicels and tags, and collect them in a basket.)

 ·  दो वंशक्रम तंत्र की कमियाँ (Limitations of two line system):-

i. अनुरक्षण बहुत कठिन होता है।

(Maintenance is very difficult.)

ii. संकर बीज की कम मात्रा उत्पन्न होती है।

(Less quantity of hybrid seed is produced.)

iii. नर बंध्यता स्त्रोत अस्थायी होता है।

(The male sterility source is unstable.)

कपास में संकर बीज के उच्च लागत के कारण (Causes of high cost of cotton hybrid seed):-

1. परम्परागत संकरण (Conventional hybridization):-

·         कपास में अधिकांश संकर इसी विधि से उत्पन्न किए जाते हैं।

(Most hybrids in cotton are produced by this method.)

·         इसमें 3 मुख्य चरण होते हैं:-

(It has of 3 main steps: -)

i. नर  मादा जनकों की पहचान करके उन्हें उगाना 

(Identification and growing of male and female parents)

ii. मादा जनक का विपुंसन 

(Emasculation of female parent)

iii. मादा जनक का परागण 

(Pollination of female parent)

·         कपास के परागकण भारी  चिपकने वाले होते हैं। प्राकृतिक रूप से मधुमक्खियों  bumble bees के द्वारा के 6% ही परपरागण होता है। इसलिए हमें हाथ द्वारा विपुंसन  परागण कराना पड़ता है जिसके लिए अधिक समयश्रम  खर्च की आवश्यकता होती है।

(Cotton pollens are heavy and adhesive. Naturally only 6% cross pollination is done by honey bees and bumble bees. Therefore, we have to done hand emasculation and hand pollination which requires more time, labor and expenditure.)

·         यदि हम नर बंध्य वंशक्रम का उपयोग करते हैं तब भी परागण तो हाथ से ही कराना पड़ता है।

(Even if we use the male sterile line, pollination has to be done by hand manually.)

2. खेती की लागत (Cultivation cost):- संकर बीज का अधिक उत्पादन लेने के लिए अधिक मात्रा में उर्वरककवकनाशियोंकीटनाशियों आदि फसल को देना पड़ता है जिससे लागत बढ़ जाती है।

(To get more production of hybrid seeds, more amount of fertilizers, fungicides, pesticides etc. has to be given to the crop, which increases the cost.)

3. बीज निर्माण में कठिनाई (Difficulty in seed setting):- द्विगुणित कपास में छोटा पुष्प आकार  ब्रिटल पुषवृन्त के कारण बीज निर्माण बहुत कम (25%) होता है।

(In diploid cotton, seed setting is very low (25%) due to the small flower size and brittle inflorescence.)

4. नैप्स  मोट्स की उपस्थिति (Presence of neps and mots)

5. ग्रो आउट परीक्षण (Grow Out Test):- GOT परीक्षण के बिना कपास के संकर बीज का प्रमाणीकारण नहीं किया जा सकता। GOT परीक्षण का काल बीज उत्पादन  अगले वर्ष बुवाई के मध्य फिट नहीं बैठता है जिससे समय पर कपास के संकर बीज की आपूर्ति करने में समस्या आती है।

(Hybrid seed of cotton cannot be certified without GOT testing. The GOT test period does not fit between seed production and sowing the next year, causing problems with timely supply of hybrid cotton seeds.)

Advances:- बाजार में उपलब्ध संकर बीज बहुत अधिक महंगा होता है क्योंकि इसका उत्पादन खर्च बहुत अधिक होता है। संकर बीज के मूल्य को कम करने के लिए संकर बीज उत्पादन में जिन उन्नत तकनीकों का उपयोग   किया जाता है, Advances कहलाती हैं। इन तकनीकों के उपयोग से प्रकार से संकर बीज का मूल्य कम कर   सकते हैं -

(Hybrid seed available in the market is very expensive because its production cost is high. Improved techniques, which are used in hybrid seed production to reduce the price of hybrid seeds are called Advances. By using these techniques we can reduce the price of hybrid seeds in 2 ways -)

i. उपज को बढ़ाकर (By increasing yield)

ii. उत्पादन खर्च को घटाकर (By reducing production cost)

कपास में संकर बीज के उत्पादन को बढ़ाने के लिए निम्न तकनीकों का उपयोग कर सकते हैं:-

(The following techniques can be used to increase the production of hybrid seeds in cotton: -)

1. नर बंध्य वंशक्रमों का उपयोग (Use of male sterile lines)

2. नियंत्रित फल निर्माण  प्रतिबंधित परागण (Controlled fruiting and Restricted pollination)

3. पादप ट्रिमिंग  प्रुनिंग (Plant trimming and pruning)

4. जनक वंशक्रमों का मिश्रित रोपण (Mixed planting of parental lines)

5. असंगजनन का उपयोग (Use of apomixis)

6. पराजेनिक पादप (Transgenic plants)

1. नर बंध्य वंशक्रमों का उपयोग (Use of male sterile lines):-

·         नर बंध्य वंशक्रमों को मादा जनक के रूप में उपयोग करने से विपुंसन का खर्च बच जाता है। परन्तु फिर भी परागण तो हाथ से ही कराना पड़ता है।

(The use of male sterile line as female parent saves the expense of emasculation. But still pollination has to be done by hand manually.)

·         CGMS:- Gossypium harkensii में CGMS वंशक्रमों को पहचाना गया है।

(CGMS lines have been identified in Gossypium harkensii.)

·         GMS:- कुल 17 GMS वंशक्रमों को पहचाना गया है। इनमें से ms5, ms6  ms14 का उपयोग India  China में किया जाता है।

(A total of 17 GMS lines have been identified. Of these, ms5, ms6 and ms14 are used in India and China.)

·         CIMS:- कुछ ऐसे रसायन हैं जो कृत्रिम रूप से नर बंध्यता को प्रेरित करते हैंइन्हें युग्मकनाशी कहते हैं।

(There are some chemicals that artificially induce male sterility, these are called gametocides.)

उदाहरण (Examples):- SMA (Sodium Methyl Arsenate), ZMA (Zinc Methyl Arsenate), NAA, MH, GA, Ethrel, FW – 450

नोट (Note):- कपास में MH  FW – 450 का उपयोग किया जाता है। MH का उपयोग upland cotton के लिए करते हैं और FW – 450 का उपयोग G. arboretum के लिए करते हैं।

(MH and FW-450 are used in cotton. MH is used for upland cotton and FW - 450 is used for G. arboretum.)

·         TGMS:- इसका उपयोग G. arboretum में किया जाता है। 18°से कम तापमान पर पौधे पूर्ण नर उर्वर होते हैं तथा 20°से अधिक तापमान पर पौधे पूर्ण नर बंध्य होते हैं।

(It is used in G. arboretum. Plants are completely male fertile at temperatures below 18°C and they are completely male sterile at temperatures above 20°C.)

2. नियंत्रित फल निर्माण  प्रतिबंधित परागण (Controlled fruiting and Restricted pollination):-

a. नियंत्रित फल निर्माण (Controlled fruiting):- विशिष्ट समय अंतरालों पर अक्रॉसित पुष्पों  उनसे बने फलों को मादा जनक पौधों से हटाते रहते हैं। इससे पोषण केवल क्रॉसित बॉल्स को ही मिलता है जिससे संकर बीज उपज बढ़ जाती है।

(At specific time intervals, the uncrossed flowers and their fruits are removed from the female parent plants. It provides nutrition only to crossed balls which increases the hybrid seed yield.)

b. प्रतिबंधित परागण (Restricted pollination):- परागण काल को 60 दिन से कम करके 30 दिन कर देते हैं। इससे कपास के संकर बीज दिसम्बर महीने में ही उपलब्ध हो जाते हैं। GOT के लिए काफी समय मिल जाता है। जिससे बाजार में संकर बीज की समय पर आपूर्ति की जा सकती है।

(Pollination period is reduced from 60 days to 30 days. This makes hybrid seeds of cotton available in the month of December. There is a lot of time for GOT. Due to which timely supply of hybrid seed can be done in the market.)

3. पादप ट्रिमिंग  प्रुनिंग (Plant trimming and pruning):-

a. पादप ट्रिमिंग (Plant trimming):- अत्यधिक वृद्धि वाली शाखाओं  पत्तियों को काटकर छोटा करने की प्रक्रिया को ट्रिमिंग कहते हैं। इससे पादप सिंचाई  पोषक आपूर्ति के प्रति अच्छी प्रतिक्रिया देता है। रोगों  कीटों का प्रकोप भी घट जाता है।

(Trimming is a process of truncation of excessive growth branches and leaves. This gives the plant good response to irrigation and nutrient supply. Outbreak of diseases and pests also decreases.)

b. पादप प्रुनिंग (Plant pruning):- वृद्धि को प्रोत्साहित करने के लिए मृत  पुरानी शाखाओं को काटकर हटा देने की प्रक्रिया को प्रुनिंग कहते हैं। इससे दूसरी  तीसरी off season crops को Manage किया जा सकता है। दूसरी फसल में परागण काल को 30 दिन से घटाकर 17 दिन किया जा सकता है। तीसरी फसल में परागण काल को 30 दिन से घटाकर 13 दिन किया जा सकता है।

(Pruning is the process of cutting and removing dead and old branches to encourage growth. With this, the second and third off season crops can be managed. In the second off season crop, the pollination period can be reduced from 30 days to 17 days. In the third off season crop, the pollination period can be reduced from 30 days to 13 days.)

4. जनक वंशक्रमों का मिश्रित रोपण (Mixed planting of parental lines):- पंक्ति रोपण विधि की बजाय यदि नर  मादा जनक पौधों का मिश्रित रोपण किया जाये तो इससे परागकणों का स्थानांतरण आसानी से बढ़ जाता है। इससे संकर बीज उपज भी बढ़ जाती है।

(If mixed planting of male and female parent plants is done instead of row planting method, it increases the transfer of pollens easily. This also increases hybrid seed yield.)

5. असंगजनन का उपयोग (Use of Apomixis):-

·         इसमें बिना अर्धसूत्री विभाजन  निषेचन के बीज का निर्माण होता है।

(In this process, seeds are formed without meiosis and fertilization.)

·         असंगजनन संकर ओज को स्थिर कर देता है। अब इन्हें एक पृथक्कृत खेत में गुणित करके इनका अनुरक्षण करते हैं।

(Apomixis fix the hybrid vigour. Now maintain them by multiplying in an isolated field.)

·         इसमें संकरण लागत शून्य होती है। संकर बीज उपज अधिक होती है।

(It has zero hybridization cost. Hybrid seed yield is high.)

·         Bt कपास बीज बहुत अधिक महंगा होता है। असंगजनित Bt संकर विकसित करने से किसानों को प्रति वर्ष नया Bt बीज खरीदने की आवश्यकता नहीं पड़ेगी।

(Bt cotton seed is very expensive. By developing apomictic Bt hybrids, farmers will not have need to buy new Bt seeds every year.)

·         इसे “One line method of hybrid development” भी कहते हैं।

(It is also called "One line method of hybrid development".)

6. पराजेनिक पादप (Transgenic plants):-

·         मार्च 2002 में भारत में Bt कपास का वाणिज्यिक खेती को मान्यता मिली।

(Commercial cultivation of Bt cotton was authorized in India in March 2002.)

·         प्रारम्भ में 3 Bt संकरों को विमोचित किया गया था:-

(Initially 3 Bt hybrids were released: -)

i. MECH – 12

ii. MECH – 162

iii. MECH – 184

·         आज तक Bt कपास के 133 से भी अधिक संकर बाजार में विमोचित हो चुके हैं।

(Till now, more than 133 hybrids of Bt cotton have been released in the market.)

·         जनक Bt वंशक्रमों का उपयोग करने से खेती पर लागत कम हो जाती है। जैसे कीटनाशियों की लागत बच जाती है।

(Using the parent Bt lines reduces costs on farming. Such as, the cost of pesticides is saved.)