M Sivasamy

A reproducible in vitro pollen germination medium for recalcitrant cereal rye pollen (Secale cereale L): Effect of tryptone

A reproducible in vitro pollen germination medium (PGM) for cereal rye is reported here using tryptone for the first time. Rye pollen is very difficult to germinate on nutrient medium being trinucleate and is classified as recalcitrant pollen. This study addresses the possibility of testing the viability of rye pollen within short time (15–20 min) using pollen germination medium (PGM). The viability of rye pollen was tested with FDA staining also. The results of both staining and in vitro pollen germination were found comparable. In this study, tryptone, a nitrogen source was used in addition to essential sugar and inorganic salts. PGM used for rye consisted of 19% maltose, 13% poly ethylene glycol 6000, 62.5 mgl−1 boric acid, 50 mgl−1 tryptone and 1% agar. During the flowering period, a pollen sterility of 3–12% was recorded. The PGM showed >93% pollen germination with intact pollen tubes at 17±1°C and pH 6–7. This tool would be useful in many pollen biotechnological aspects such as pollen transformation, overcoming crossability barriers especially in wheat x rye wide hybridization etc.

An improved in vitro germination medium for recalcitrant bread wheat (Triticum aestivum L.) pollen

There is no robust and quick technique available for testing germination of wheat pollen. In this study, Brewbaker and Kwack (BK) pollen germination medium (PGM) was adjusted with-amino caproic acid (EACA), peptone water and maltose to develop an improved medium for wheat. Germination of pollen in this PGM ranged from 92% to 98.2% depending upon genotype pollen germination media (PGM). This is the first report of PGM which has >95% wheat pollen germination in vitro.

Central Wheat Hs562'-A High Yielding Wheat Variety for Timely Sown Production Conditions of Northern Hill Zone

Dharam Pal1*, Madhu Patial1, KV Prabhu2, J Kumar1,7, Santosh Watpade1, RN Yadav3, Sanjay Kumar2, RK Sharma2, GP Singh2,8, Rajbir Yadav2, Vinod2, Anju M Singh2, SV Sai Prasad4, IS Solanki6,9, M Sivasamy5, JB Sharma2, PK Singh2, Neelu Jain2, Niharika Mallik2, Kiran Gaikwad2, Tapas Ranjan Das6, Vikas5, Jaya Prakash5, JB Singh2, Divya Ambati4, Vaibhav Singh2, AN Mishra4, Shivadhar2 and Ajay Arora2 1ICAR-IARI, Regional Station, Shimla, India 2ICAR-Indian Agricultural Research Institute, New Delhi, India 3ICAR-Indian Agricultural Research Institute, Regional Station, Karnal, India 4ICAR-Indian Agricultural Research Institute, Regional Station, Indore, India 5ICAR-Indian Agricultural Research Institute, Regional Station,Wellington, India 6ICAR-Indian Agricultural Research Institute, Regional Station,Pusa, India 7ICAR-NIBSM, Raipur, India 8ICAR-Indian Institute of Wheat and Barley Research, Karnal, India 9ICAR-Krishi Bhawan, New Delhi

Protein marker as an easy tool to detect Secale cereal - derived linked genes Sr31, Lr26, Yr9 and Pm8 in wheat

The high yielding potential associated with IRS. IBL translocation involving the short arm of rye chromosome 1R and the long arm of wheat chromosome IB were well exploited world over for developing disease resistant and high yielding wheat varieties. This was due to the translocation of the effective disease resistance linked genes Sr31 for resistance to stem rust (P. graminis f. sp. tritici), Lr26 for resistance to leaf rust (caused by Puccinia triticinia), Yr9 for resistance to stripe rust (P. striiformis f. sp. tritici), Pm8 for resistance against powdery mildew (caused by Erisiphe graminis f. sp. tritici) along with useful agronomic traits. However now virulent pathotypes have been reported which has overcome these rust resistance genes. The Sr31 gene complex has close linkage with the genes controlling secalins (Sec-1). Thus Sec-1 acts as a marker for the identification of Sr31, Lr26, Yr9 and Pm8 genes. SDS -PAGE was used to examine the presence of IBL. IRS translocation in six Indian wheat genotypes viz., HP 1205, HD2329, HD 2285, WH 147, Lok-1 and J 24 introgressed with Sr31+ gene complex with the aim to eliminate the lines carrying these genes, since it is tightly linked to poor baking quality. The SDS - PAGE results showed that all the lines carry Sec-l band and are therefore likely to carry the IBL. IRS translocation and the linked genes Sr31, Lr26, Yr9 and Pm8. This technique could be well exploited to detect the presence of linked genes Sr31, Lr26, Yr9 and Pm8 in wheat cultivars as it is an easy, efficient, faster and economical tool to eliminate the lines with IBL. 1RS translocation and developing wheat varieties for better end use quality and reducing the risk to Ug99 stem rust race threat