Cane Height Research Articles

Effect of Different Levels and Sources of Sulphur Application on Sugarcane Production

The experiments were conducted at two locations in Haryana. The treatments consisted of application of Cosavet Fertis (a sulphur containing fertilizer in Water Dispersible Granules (WDG) formulation) @ 18 kg S/ha (½ at sowing + ½ at 75 days after sowing (DAS) or (½ at 30 DAS + ½ at 75 DAS), Cosavet Fertis @ 13.5 kg S/ha (½ at sowing + ½ at 75 DAS) or (½ at 30 DAS + ½ at 75 DAS), Gypsum @ 25 kg S/ha and Control (No sulphur). At both the locations, the application of Cosavet Fertis @ 18 or 13.5 kg S/ha (½ at sowing + ½ at 75 DAS) or (½ at 30 DAS + ½ at 75 DAS) and Gypsum @ 25 kg S/ha produced significantly higher yield than control (No sulphur) and enhanced cane height, cane diameter, Number of millable canes over control. The increase the yield with the application of S ranged from 5.2 to 10.5% over control. These treatment gave Rs. 2938–5664 to additional return over control and cost benefit ratio (C:BR) ranged from 1.78 to 9.85. Application of Cosavet Fertis @ 18 or 13.5 kg S/ha applied at ½ at sowing + ½ at 75 DAS or ½ at 30 DAS + ½ at 75 DAS, did not significantly increase the cane yield and yield attributing character over Gypsum @ 25 kg S/ha.

OPTIMIUM INTER-ROW SPACING AND NUMBER OF PLOUGHINGS FOR TWO PROMISING SUGARCANE VARIETES

The present work was conducted at El-Mattana Agricultural Research Station, Luxor Governorate during 2008/2009 and 2009/2010 seasons to assess the optimum inter-row spacing and number of ploughings for two promising varieties. The study included twelve treatments, which were the combinations among three enter-row spacing (80, 100 and 120 cm) and two ploughing treatments (two or three passes) for the two promising sugar cane varieties namely G.95-19 and G.95-21. Split-split plot design with four replications was used in both seasons. The obtained results showed that the examined enter-row spacing significantly affected the number of millable canes/fed, millable cane height and diameter, as well as total soluble solids, sucrose, sugar recovery percentages, cane and sugar yields/fed. The closest enter-row spacing (80 cm) gave the highest values of all studied traits. Moreover, insignificant difference was found between 80 and 100 cm inter-row spacing in the number of millable cane/fed, millable cane height, sucrose and sugar yield. Number of millable canes/fed, millable cane height, stalk diameter, total soluble solids and cane yield were significantly affected by ploughing number. Furthermore, practicing three ploughing passes resulted in the highest values of the aforementioned characters, except for stalk diameter. The promising sugarcane variety G.95-21 significantly surpassed G.95-19 the other promising one in number of millable canes/fed, millable stalk height, millable cane diameter, total soluble solids percentage and cane yield/fed. Under conditions of the present investigation, planting G.95-21 sugarcane variety in rows spaced at 100 cm along with three ploughings can be recommended to obtain the highest cane and sugar yield/fed.

Performance of Elite Early Maturing Sugarcane Clones for Yield and Quality Traits During Varietal Selection Process

Performance of fourteen early maturing sugarcane clones developed through fuzz was assessed along with two local checks and one promising variety as standards at Sugarcane Research Station, Tamil Nadu Agricultural University, Sirugamani during 2012-13. Data were recorded for germination, economic shoot, cane thickness, cane height, number of internodes/ plant, internode length, cane yield, Brix (%), Pol ( %), purity (%), CCS (%) and sugar yield. Analysis of variance revealed highly significant differences among test clones for cane yield, sugar yield and its attributing traits. On the basis of overall performance, three test clones, namely Si 07-101, Si 07-017 and Si 07-082 showed good performance in respect of cane yield with average mean values of 134.60, 132.30 and 131.10 t/ha respectively against the best standard CoSi(SC) 6 (127.30 t/ha). While, the test clone Si 07-102 produced the lowest cane yield of 91.20 t/ha. The highest average mean sugar yield was observed in Si 07-131 (18.54 t/ ha), Si 07-017 (18.14 t/ah), Si 07-082 (17.21 t/ha) and Si 07-101 (17.00 t/ha) against the best standard TNAU Sugarcane Si 7 (16.01 t/ha). However, the test clone Si 07-102 gave the lowest sugar yield of 9.46 t/ha against the standards. On the basis of over all performance it was concluded that the test clones Si 07-017, Si 07-082, Si 07-101 and Si 07-131 need to be forwarded to next selection stage for further progression and testing.

Cane Length Influence on the Plantar Pressure Distribution of Adult Hemiplegia Patients

[Purpose] The purpose of this study was to investigate changes in plantar pressure distribution on the affected side related to arm length ratio to height of adult hemiplegia patients during gait. [Subjects] Twenty-four individuals with stroke were included in this study. [Methods] Subjects were divided into two groups according to the ratio of arm length to total height of each individual: group 1 had a ratio of less than 50% and group 2 had a ratio equal to or greater than 50%. The F-scan system was used to investigate the foot pressures of both feet with data captured during three strides. [Results] Group 1 showed greater increase in contact width, contact pressure, and peak contact pressure of the hind foot of the affected side. [Conclusion] With the use of a cane height standardized to the greater trochanter, group 1 was more effective than group 2 at increasing foot pressures of the hind foot on the affected side of stroke patients. The adjustment of cane length according to the individual's ratio of arm length to height, because of unique physical characteristics of individuals should be considered for patients with stroke who use a cane daily.

Studies on variation in interspecific hybrids of Saccharum

The extent and pattern of variation were studied in the seven crosses of F1 population of improved S. officinarum x Interspecific hybrids of Saccharum involving one cultivated S. barberi and two wild species S. spontaneum and S. robustum. The study revealed the superiority of all the crosses for cane population and presence of substantial variability for further effective selection and utilization. In general the hybrid progenies were observed to be thin. High heterotic vigour was observed for cane height, which will be of use to maintain yield potential. Mean performance of the crosses for H.R. Brix% was low, which needs further improvement. The average NMC in crosses in general were less when compared to male parent ISH 154 and were high in comparison with pistil parent like Co 87010. The crosses involving commercial hybrids as a pistil parent and S.robustum as a donar in the male parent namely Co 87010 X ISH 29 was superior for single cane weight and cane yield. There was an improvement in cane diameter and H.R. Brix % by utilizing clone ISH 29 from S. robustum group as a male parent, whereas, S. barberi involving clone ISH 154 helps in increasing the cane population and millable cane height in respective crosses. In general, clones with high number of millable canes, moderate brix, good vigour and medium thick canes were also observed which can be exploited further.

Determination of the best blackberry cultivar using various statistical techniques

This study was conducted to determine the best blackberry cultivar using jointly various statistical techniques such as Chi-square, G, and Correspondence statistics. For this aim, data of pomological traits such as fruit weight, cane number, cane diameter, cane height, cane yield per plant of Ness, Cherokee, Arapaho, Chester Thornless, Navaho, Black Satin, Dirksen Thornless and Jumbo cultivars were collected during 2002-2006. With respect to chi-square and G statistics, associations between cultivar and each pomological trait (fruit weight, cane number, cane diameter, cane height, and cane yield per plant) were found more significant (P < 0.0001). The relationship between year and cane number was significant (P < 0.0001 and year and cane diameter was significant (P < 0.05). The highest cane number was produced in 2004, followed by 2005. The relationship between fruit weight and cane diameter or cane yield per plant were more significant (P < 0.0001). Although Blacksatin and Jumbo blackberry cultivars had the highest cane number, Chester Thornless from blackberry cultivars had the highest cane diameter, the highest cane yield per plant and the highest fruit weight. It was concluded that Chester Thornless cultivar was the most appropriate cultivar for Central Anatolia region. Key words: Adaptation, blackberry, cane, fruit, Chi-square statistic, G statistic, correspondence analysis.

Increasing the efficacy of Trichoderma harzianum for nutrient uptake and control of red rot in sugarcane

The application of Trichoderma multiplied culture (TMC) of T. harzianum strain Th 37 @ 20 kg/ha on the stubbles at the ratoon initiation stage increased the availability of nitrogen (N), phosphorus (P) and potassium (K) by 27, 65 and 44%, respectively. Availability of some of the micronutrients viz., Cu, Fe, Mn and Zn were also enhanced, respectively by 6, 100, 79 and 66%. There was a considerable increase in organic carbon (55%) with concomitant decrease in soil pH (6%).There was significant difference in nutrient uptake between highly red rot susceptible variety (CoLk 7710) and moderately resistant variety (CoS 96268). The increase of N uptake was more in susceptible CoLk 7701 (69%) where as the uptake was only 45% in moderately resistant CoS 96268. P uptake increased by 96% in CoLk 7701 and 69% in CoS 96268. K uptake increased 128% over control of CoLk 7701 and 59% in CoS 96268. The level of protection against red rot increased up to 78% in combination with TMC + salicylic acid (SA) and 86% with metabolites + SA where as the protection was 60 and 71%, respectively with TMC and metabolites. Application of TMC + SA resulted in significant growth promotion through improvement in ratoon initiation (15%), number of tillers (8%), cane height (5%), girth (4%), number of internode (8%), length of internode (2%), single cane weight (5%) and number of millable cane (4%) which was reflected in the improvement in average yield by 23%. Key words: Sugarcane, Trichoderma harzianum, red rot, Colletotrichum falcatum, biocontrol, nutrient uptake, salicylic acid, agrochemicals, growth promotion, management.

Carbon Dioxide Enrichment May Increase Yield of Field-grown Red Raspberry under High Tunnels

The objectives of this preliminary study were to optimize a carbon dioxide (CO2) application system for field-grown raspberry (Rubus ideaus) under high tunnels and then to compare plant photosynthesis, growth, and fruit yield with and without CO2. Based on plant photosynthesis measures before CO2 application, we placed the drip irrigation tape to apply CO2 in the middle of the plant canopy at 100 cm aboveground and split daily CO2 application from 0700 to 1100 hr and 1400 to 1800 hr. In the morning hours, CO2 concentration in the tunnel was 18% higher than in the afternoon; wind speed often increased later in the day, which may have moved the CO2 even in the tunnel. We maintained an average CO2 concentration of 436 ppm for 4 months, applying about 25 tons of CO2. In tunnels enriched with CO2, yield and berry size from plots 20 ft in length increased 12% and 5%, respectively, compared with untreated tunnels. We measured no corresponding differential response in the number of 6-oz baskets harvested from the full tunnel, leaf CO2 assimilation, stomatal conductance (gS), or fluorescence, raspberry cane height, pruned cane biomass, cane diameter, or carbohydrate content of the fruit after CO2 application. Documenting potential plant physiological changes should therefore be a focus of future research.

Simulación de un algoritmo para controlar el nivel en tolva ante alimentación discontinua de caña

The current control methods for cane transport and preparation cause serious discontinuity problems in the cane supply to the milling train in Cuban sugar industry. The broad spread of frequency converters technology for speed control of induction motors allows proposing the usage of entry conveyors speed as the main control action to regulate the buffer chute height. This article presents an alternative control strategy by means of speed conveyors which considers the sugar cane height in the elevator conveyor as an input multiplicative disturbance. A sliding mode algorithm for set-point adaptation is proposed in order to delimit the chute level oscillations caused by the irregular cane supply. The proposed method only requires feedback of accessible variables and it is robust to cane density changes and measurement noise. Furthermore, its implementation is extremely easy for PID speed control loops.

Vegetative Growth and Flowering of Primocane Raspberry ‘Ariadne’ as Affected by Prohexadione–calcium Treatments

Maintaining an appropriate balance between vegetative and generative growth is a prerequisite for profitable raspberry (Rubus idaeus L.) production. The objective of our study was to test the effect of prohexadione–calcium (ProCa) on vegetative growth and flowering of primocane fruiting red raspberry ‘Ariadne’ in greenhouse conditions. ProCa was applied either once or twice in a concentration of 100 ppm or 200 ppm. Double applications of ProCa reduced cane height by 33 cm (100 ppm) or by 46 cm (200 ppm). Growth reduction was the result of shortening of the internodes, because total node number in plants was unaffected. Furthermore, cane diameter was reduced in plants treated with 200 ppm ProCa. ProCa treatments reduced the total aboveground dry weight by 32% to 55% but did not affect the allocation of dry weight into different plant parts. All ProCa treatments reduced the number of flowers by 22% to 42%. In conclusion, ProCa proved effective in controlling vegetative growth of red raspberry. However, because the number of flowers was reduced, ProCa cannot be recommended for growth regulation of primocane fruiting raspberry without further studies.

Production of high yielding red raspberry long canes in a Northern climate

Techniques for the production of raspberry long canes with high yield potential were studied on a research station and in two commercial nurseries in South Norway. Potted ‘Glen Ample’ plants were grown in the open and in polyethylene greenhouses during two seasons in order to optimize cultural practices. Dates of propagation and transfer to the production sites were varied. Following cold storage from December to early June, the canes were tipped (cut) at 160 cm height and grown in open plastic tunnels in the fruiting season for the evaluation of growth and yield performance. Remarkable berry yields of 1.5–3.8 kg per plant (cane) were regularly achieved. When grown in the open, later starts than June 1 (June 15 and July 1) successively reduced yields. On the other hand, an earlier start involves risks of growth cessation due to low spring temperature. When grown in greenhouses, high yields were still possible when plants were transferred from propagation conditions as late as July 1, although optimal yields of nearly 4 kg per plant were obtained with transfer on June 15. In a year with unusually high summer temperatures, the yields of canes produced in the open and in greenhouses did not vary significantly, whereas in the second year with normal summer temperatures, canes produced in greenhouses consistently out-yielded those produced in the open by about 1 kg per cane. Regression analyses revealed that high yields were associated with fruiting cane architecture traits such as cane height, number and length of laterals, and a low proportion of dormant buds. The single most important component was lateral length which alone accounted for 82% of the yield variation. Since lateral lengths increased from the shoot tip towards the base, cane heights in excess of 2 m are required for the attainment of top yields as the uppermost nodes with short and low-yielding laterals then can be eliminated by tipping.

Optimization of Gamma Radiation Dose for Induction of Genetic Variation in Sugarcane (Saccharum spp) Callus and Regenerated Shoot Cultures

Callus cultures were established in three commercial sugarcane varieties viz., CoJ 64, CoJ 83 and CoJ 86 from spindle explants on MS + 2,4-D (4 mg l−1) + BAP (0.5 mg l−1) medium. Shoots were regenerated from two-month-old calli on MS + BAP (0.5 mg l−1) medium. Callus and callus derived shoots were treated with gamma (γ) radiation at 20, 40, 60 and 80 Gray (Gy). Per cent shoot regeneration from y-irradiated calli in the three varieties ranged from 90 to 93.8 at 20 Gy, 83.3 to 87.5 at 40 Gy, 30 to 36.4 at 60 Gy and 0 at 80 Gy. Upon irradiating shoots, subsequent shoot proliferation in the three varieties ranged from 90.9 to 93.1% at 20 Gy, 82.6 to 84.0% at 40 Gy and 27 to 32.3% at 60 Gy, whereas 80 Gy dose was 100% lethal. Thus, 60 Gy dose of y-radiation was found to be optimum for carrying out mutagenesis of both callus and callus derived shoots. In the field, different irradiated clones of the same variety exhibited huge variability with respect to number of canes, cane girth, cane height and sucrose content.

Estimation of fruit weight by cane traits for eight American blackberries (Rubus fructicosus L.) cultivars

2 values) in MRA were found to be Black Satin (99.40%), Ness (99.16%), Navaho (96.46%), Dirksen Thornless (96.22%), Chester Thornless (91.92%), and Cv. Jumbo (91.26%), which meant that most (almost 100%) variation in fruit weight for these cultivars was explained by the number of cane, cane height, cane diameter, and cane yield. However, corresponding values for Arapaho and Cherokee cultivars was estimated as 2.88% and 33.2% of the total variation in fruit weight. It was concluded that number of canes had positive-significant effect on fruit weights of Dirksen Thornless (P < 0.001) and Cv. Jumbo (P<0.01), but negative-significant effect on that of Black Satin (P < 0.001). Cane height had positive-significant effect on fruit weights of Black Satin (P < 0.001) and Ness (P<0.001) cultivars, but negative-significant effect on cv. Chester Thornless (P < 0.001) and Dirksen Thornless (P < 0.01). Cane diameter had positive-significant effect on fruit weights of Black Satin (P < 0.001) and Chester Thornless (P < 0.01), Navaho (P < 0.05), Ness (P < 0.01) cultivars, whereas it had negative-significant effect on cv. Jumbo (P < 0.05). Cane yield had positive-significant effect on fruit weight of only Cv. Jumbo, but negative-significant effect on cv. Black Satin (P < 0.001), Chester Thornless (P < 0.01), Dirksen Thornless (P < 0.001), Navaho (P < 0.001) and Ness (P < 0.001). It was concluded that cane traits with the positive and negative effect on fruit weight provide useful clues for breeding proposes to improve fruit weight.

Estimation of fruit weight by cane traits for various raspberries (Rubus ideaus L.) cultivars

Raspberries are an important commercial fruit crop, widely grown in all temperate regions of the world. The raspberries contain significant amounts of polyphenol antioxidants such as anthocyanin pigments linked to potential health protection against several human diseases. The aim of this study was to estimate fruit weight by their cane traits (the number of canes, cane height, cane diameter, and cane yield) for Aksu Red, Canby, Heritage I, Heritage II, Holland Dwarf, Nuburg, Rubin, Summit, Tulameen, and Willamette cultivars grown in Central Anatolia region during 2002 - 2006. For this aim, average fruit weight (dependent variable) for each cultivar was estimated by independent variables such as the number of cane, cane height, cane diameter, and cane yield using Multiple Regression Analysis (MRA). The results clearly show that cultivars having the best fit (giving the best R2 values and the lowest RMSE) in MRA were: Holland Dwarf (99.64%), followed by Heritage I (99.06%), Summit (98.6%) Aksu Red (92.82%), Willamette (92.68%), Heritage I (90.46%), Rubin (90.28%) and Canby (85.45%). Multiple Regression Modeling gave good results for these cultivars. However, R2 values of these cultivars were found higher (better fit) than those of Nuburg and Tulameen cultivars. It was concluded that the number of canes had significant negative effect on fruit weights of Heritage (P cultivars, but significant positive effect on only fruit weight of Rubin cultivar (P while it had significant negative effect on fruit weights of Canby (P 0.001), and Tulameen (P (P all cane traits were statistically significant (P improve fruit weight.

Estimation of fruit weight by cane traits for various raspberries (Rubus ideaus L.) cultivars

Raspberries are an important commercial fruit crop, widely grown in all temperate regions of the world. The raspberries contain significant amounts of polyphenol antioxidants such as anthocyanin pigments linked to potential health protection against several human diseases. The aim of this study was to estimate fruit weight by their cane traits (the number of canes, cane height, cane diameter, and cane yield) for Aksu Red, Canby, Heritage I, Heritage II, Holland Dwarf, Nuburg, Rubin, Summit, Tulameen, and Willamette cultivars grown in Central Anatolia region during 2002 - 2006. For this aim, average fruit weight (dependent variable) for each cultivar was estimated by independent variables such as the number of cane, cane height, cane diameter, and cane yield using Multiple Regression Analysis (MRA). The results clearly show that cultivars having the best fit (giving the best R2 values and the lowest RMSE) in MRA were: Holland Dwarf (99.64%), followed by Heritage I (99.06%), Summit (98.6%) Aksu Red (92.82%), Willamette (92.68%), Heritage I (90.46%), Rubin (90.28%) and Canby (85.45%). Multiple Regression Modeling gave good results for these cultivars. However, R2 values of these cultivars were found higher (better fit) than those of Nuburg and Tulameen cultivars. It was concluded that the number of canes had significant negative effect on fruit weights of Heritage (P cultivars, but significant positive effect on only fruit weight of Rubin cultivar (P while it had significant negative effect on fruit weights of Canby (P 0.001), and Tulameen (P (P all cane traits were statistically significant (P improve fruit weight.

In vitro induction and characterization of somaclonal variation for red rot and other agronomic traits in sugarcane

In the present investigation, optimal media compositions for enhancing the callus induction and subsequent plant regeneration were worked out in sugarcane (Saccharum spp. complex). The field grown somaclones were characterized for yield and quality contributing traits in comparison to donor variety CoJ 88. The MS + 2,4-D (4.0 mg/l) + kin (0.5 mg/l) + sucrose (30 g/l) was found to be the best for the callus induction among the nine media compositions used. The highest shoot regeneration was 34.65% on MS + BAP (0.5 mg/l) followed by 31.07% on MS + IAA (2.0 mg/l) + kin (0.5 mg/l) and the least 11.80% on MS + BAP (2.0 mg/l). The shoot elongation was optimum on MS + IBA (5.0 mg/l). The rooting was carried on MS + NAA (3.0 mg/l) + IBA (2.0 mg/l) + sucrose (70 g/l). The somaclones, on field evaluation, exhibited huge variability for characters viz., tiller number at 120 days of field transfer, number of millable canes, cane height, number of nodes and internodal length at time of harvest and also for HR Brix at 240 and 300 days after field transfer. In R0 generation, the variations induced for the characters such as stalk height after 120 days, HR Brix after 240 and 300 days of field transfer were negatively skewed with most of somaclones having values higher than the population mean values thereby offering adequate scope for improvement cane and quality. Elite somaclones marked for each trait were reported. Out of 228 somaclones inoculated with Cf 08 pathotype of red rot in R1, three were resistant, four were moderately resistant and 221 somaclones showed variable degree of susceptibility, whereas, to Cf 03 pathotype, fourteen were resistant, nineteen were moderately resistant and 195 showed variable degree of susceptibility. Three somaclones exhibited moderate resistance (MR) to both the pathotypes, whereas, donor variety CoJ 88 showed susceptible reaction. These somaclones will further enhance the germplasm for sugarcane breeding.

Harvest index — sugar yield in sugarcane genetic stocks and its association with yield attributes, nutrients ratio and sucrose

Harvest index in sugarcane based on sugar yield were studied in 30 sugarcane genetic stocks. Statistically significant differences of harvest index — sugar yield among clones, among stages and significant interaction between clone x stage were observed at 0.1% level. The wide variation of harvest index-sugar yield was between 0.061 in Co 62399 to 0.108 in CoC 671 at 10 months. Clones showing high harvest index was observed in CoC 671, B 37172, Co 62174, Co 418, Co 7704, CoA 7601, Co 7508, Co 7204, Co 678, Co 6806, Co 7717, and Co 997 and low harvest index was observed in Co 62399, CP 44-101, Co 1148, Co 617, CoJ 64, Co 62101, NCo 310, H 50-7209, Co 775, Co 419 and Co 975. Harvest index was increased from 0.081 at 10 months to 0.086 at 12 months. Harvest index-sugar yield had significant positive correlations with leaf N/S, N/Cl, N/Na, cations/anions, sheath N/S ratio, sheath cations minus anions, sucrose % juice and sugar yield – 8, 10 and 12 months, internodes numbers, cane volume, cane height, cane thickeness, cane wegith, harvest index — sugar yield at 10 and 12 months. There were significant negative correlations of harvest index-sugar yield with sheath N/P and N/Si ratios. Harvest index-sugar yield at 10 and 12 months had no associations with leaf N/K, N/P, N/Ca, N/Mg ratios, cations minus anions, sheath N/K, N/Ca, N/Mg, N/Cl, N/Na ratios and culm basic density.

Cane yield and quality characters of some promising somaclonal variants of sugarcane

Six tissue culture derived sugarcane somaclones TC-434, TC-435, TC-436, TC-237 and TC-045 from CoC671 and somaclone number TC-338 from Co7219 developed by Biotechnology section of Vasahtdada Sugar Institute, Pune were evaluated for their agronomical and quality attributes during suru season. Somaclone TC-435 gave higher cane yield at 12 months crop age over CoC 671. Somaclone TC-435 had significantly higher millable cane height and number of internodes than that of donor parent CoC671 .Tillering ratio at 120 days was found to be significantly higher in somaclones TC-434 and TC-045 as compared to the donor parent CoC 671. Somaclones TC-045 and TC-434 had maximum sugar content, showing increasing trend from 10th to 12th month crop age. Brix value about 23 was recorded in somaclones TC-237, TC-436 and TC-434 at the age of 12 months. Increasing trend in sugar recovery from 10th month onward was found in somaclones TC-045, TC-434 and TC-435 indicating their earliness in sugar recovery and suitability for early crush if planted in sum season. These somaclones showed higher values of CCS i.e., more than 15 % at 12 months. The promising somaclones are being evaluated in different agro-climatic zones.

Correlation and path analysis in sugarcane ratoon

The experiment was planted with fourteen early maturing high sugar genotypes along with two standards (CoJ64 and CoS687) during spring season of 2003 in randomized block design with plot size of 10 × 3.75 m2 in three replications, which was harvested during 2004 and ratoon was maintained to study the correlation and path analysis among different agronomic as well as quality characters with ratoon yield. The results indicated that the variance for juice quality trait is high. All the quality parameters like juice brix, sucrose per cent in juice and commercial cane sugar percent (CCS%) had highly positive and significant genotypic correlation with Pol percent in cane during November. Among the characters studied, number of millable canes (NMC), single cane weight and cane height showed significant positive correlation with ratoon yield and sugar tonnes per hectare (STH) but there was a weak negative correlation between NMC and single cane weight. Path analysis study reveled that two characters namely NMC and single cane weight showed significant positive direct contribution towards cane yield. This cane weight was contributed by cane height to cane yield. Although all the characters which showed significant positive correlation were important but on the basis of path analysis NMC and single cane weight had contributed more for ratoon yield. Therefore, for selection of high ratoon yield in early maturing genotypes more emphasis on NMC and single cane weight would be of much importance.

Leaf nitrogen — sodium ratio in sugarcane clones and its associations with other parameters at grand growth period

Leaf N/Na ratio had a range of 3.64 in CP 44-101 to 6.09 in Co 6806 as per variety mean and their differences were significant. The wide variation of leaf N/Na ratio was between 2.54 in Co 1148 at 7 months to 7.86 in CoA 7601 at 4 months. High leaf N/Na ratio were observed in Co 6806, Co C 671, Co 7508, Co 7204, Co617, Co A 7601, Co 7201,Co 7717, Co 740, Co 853, Co 6304, while clones recorded low N/Naratio were CP 44–101, Co 62399, Co 1148, Co 975, Co 7704, H 50–7209, Co 997, Co 62101, Co 62175, Co J 64 and Co 775. Statistically significant decreas & of leaf N/Na ratio between stages were observed from 6.21 at 4 months to 3.42 at 7 months. The interactions-between clones x stages were also significant at 0.1 % level. The associations of leaf N/Na ratio were significant and positive with leaf N/P, N/K, N/Ca, N/Mg, N/S, N/C1, N/ Si ratios, sucrose % juice at 10 and 12 months, cane yield at 10 and 12 months, sugar yield at 8, 10 and 12 months, cane volume, cane height, cane thickness, cane weight, harvest index-sugar yield-8,10 and 12 months both on fresh weight and dry weight basis. There was a significant negative association between leaf N/Na ratio and leaf cations minus anions. However, leaf N/Na ratio had no effect on at any one stage with leaf cations/anions ratio, sheath N/P, N/K, N/Ca, N/Mg, N/S, N/C1, N/Na, N/Si, cations/anions ratio, cations minus anions, internodes numbers, stalk numbers, cane density, culm bulk density, harvest index-cane yield, harvest index-CCS %, harvest index-sucrose % juice-10 and 12 months both on dry weight and fresh weight basis.