Ludhiana June 7
Large farm-to-farm and plot-to-plot variations in nitrogen-supplying capacity of soil make the situation complex and broad-based blanket recommendations do not always lead to efficient fertiliser use.

According to Dr Bijay Singh, Dr Yadvinder Singh and Dr Varinderpal Singh of department of soils, Punjab Agricultural University, in recent years a leaf colour chart (LCC) has been developed that allows measuring crop nitrogen demand simply by matching leaf colour. Green colour is an estimate of chlorophyll content of leaves, which is related to nitrogen content and can help in determining time of fertiliser nitrogen application to the crop.

Explaining leaf colour chart, Bijay Singh said it is a high quality plastic strip (8” x 3”) with different shades of green colour and has been developed through collaboration of the International Rice Research Institute (IRRI) with agricultural research systems of several countries in Asia. It consists of six green colour shades ranging from light yellowish green (number 1) to dark green (Number 6). Colour strips fabricated with veins resemble those of rice leaves and help while matching colour. It is an ideal tool to optimise nitrogen use at reasonably high yield levels, irrespective of application of organic manures, crop residues, and nitrogen carry over from previous season. LCC can be purchased from department of soils, Punjab Agricultural University, Ludhiana at the cost of about Rs 27 per piece.

Spelling out the use of the LCC, Yadvinder Singh said 25-kg urea should be applied as a basal dose at the time of last puddling. Then LCC readings are taken from 14 days after transplanting till crop just starts to flower. Readings are taken at 7-10 days interval. The colour of the youngest fully-expanded leaf of the selected plant or hill is compared with the strips of the LCC.

The colour of the topmost fully expanded leaf reflects the nitrogen status of rice plants. Leaf colour should be compared with LCC under shade of one’s body because LCC readings are affected by sun’s angle and sunlight intensity. For this 9 am to 10 am in morning and 4 pm to 5 pm in evening is the appropriate time. If more than five leaves read below a set critical shade 4, 25-kg urea should be applied on the same day. This process is repeated every 7 to 10 days and 25-kg urea is applied if colour shade comes below critical LCC value 4.

According to Dr Varinderpal Singh, 14 per cent of the on-farm experiments, it has been noticed that farmer’s harvested equivalent or higher yields with the adoption of LCC-based technology in comparison with farmer’s practice while applying a single nitrogen dose after a basal dose of 25 kg nitrogen per acre. The data also suggests that the notion of applying nitrogen fertilisers before 42 days of transplanting will hold good, only if 120 kg N ha -1 or more fertiliser nitrogen is applied to rice, as only then it leads to rice yield similar to that obtained by need-based nitrogen applications, which are generally less than the blanket recommendation. Rice responds to nitrogen applications even after 55 days of transplanting if leaf colour fell below LCC shade 4.

On limitations of LCC, he said present recommendations hold good for all rice cultivators except hybrids and basmati rice, which still needs standardisation.

While using LCC due care should be taken to avoid any water or nutritional stress. Irrigation and nutrients other than nitrogen should be given as recommended. Plant infested with diseases or insects should not be selected for matching colour with leaf colour chart. 

Ludhiana, June 7
Guru Gyan Day was observed at Green Land Senior Secondary Public School today. All the classrooms wore the look of temples. The students paid obeisance to their teachers and books. The students sought the blessings of their teachers by touching their feet.

Shakti Public School manager Bhupinder Kapoor felicitates meritorious Class XII students of the school in Machhiwara on Thursday. — A Tribune photograph

Director-cum-chairman of the school Rajesh Rudhra said this will imbibe the value of honouring and respecting the teachers in the students. Guru Gyan Day was also simultaneously observed at Green Land Convent School, Dugri Phase II; Green Land Convent School, Civil City; Green Land Convent School, New Subhash Nagar and Green Land Convent School, Chandigarh Road.

Laurels

Jaspriya Sandhu of DAV Public School has brought laurels to the city by bagging 34th position in the All-India Pre-medical Test (AIPMT) conducted by the CBSE.

Healthy living programme

A programme was held at Arya Samaj Gurukul College, Model Town, yesterday. Nearly 70 students were imparted education and training on “Now to live healthy without medicines”.

The programme was conducted by S.R. Mittal of Nature Cure Education Trust.

The principal appreciated the presentation and utility of the programme for the welfare of the students. Charts containing material on this subject were given to the college for circulation among the students.

University topper

Priyanka Sharma of Guru Nanak Girls College, Model Town, has topped Panjab University by securing 461/550 marks in B.Com I.

Excellent results

Postgraduate students of Satish Chander Dhawan Government College performed well in the M.Com (semester III) conducted by Panjab University. Chandani stood first in the college, securing 78.57 per cent marks, Nidhi second with 77.89 per cent marks followed by Sarika Bhalla with 78.17 per cent marks.

JAGRAON
Good result

In the elementary teachers training (semester l) result declared by the State Council of Educational Research and Training, students of the District Institute of Education and Training (DIET), Jagraon, performed well.

Out of the 87 students, 83 students were declared passed. Navjeet Kaur, Kusum Singla and Veerpal Kaur got first, second and third positions, respectively, by obtaining 411, 410 and 409 marks out of 550.

Machhiwara
Shakti school students excel

Students of Shakti Public Senior Secondary School, Machhiwara, bagged four positions in the merit list of Class XII students which was released by Punjab School Education Board, Mohali, this afternoon. Among the meritorious students of this school, Manjeet Kaur got rank 18 in the state by securing 88.4 per cent marks. Mandeep Kaur, Harkamal Kaur and Navpreet Kaur were on ranks 28, 53 and 108 respectively, in the state. School manager Bhupinder Kapoor congratulated the students.