Monitoring Sugarcane Smut on Major Cane Varieties in PT. Perkebunan Nusantara X (PTPN X), Indonesia

Monitoring Sugarcane Smut on Major Cane Varieties in PT. Perkebunan Nusantara X (PTPN X) Cane Plantation, Indonesia Dita Widi Atmaja*, Sunaryo N, Moch. Ma’ruf, Sabar D. Komarrudin, Purnomo Aji, Syahrial Koto and Muliah Jengkol Sugar Research Center, Perkebunan Nusantara X, Ltd. Jengkol, Plosokidul, Plosoklaten, Kabupaten Kediri 64175 *Corresponding author. E-mail : dita.viro@gmail.com

ABSTRACT Sugarcane smut is caused by the fungus Sporisorium scitamineum. The disease occurs worldwide and covers most of the sugarcane producing countries.

This research was conducted in all sugarcane plantation areas of PTPN X in East Java with 63 field samples from August 2016 until April 2017. The aim of this study was to monitor sugarcane smut infection on six major varieties in PTPN X field area.

The observation method was carried out by taking 10 samples of 10 m row with the row distance being 5 to 10 rows. Visual observation was conducted to record smut infection by counting the stools showing black “whip” structure. Results showed that Bululawang variety is the most susceptible to smut infection compared to all varieties observed. Continuous availability of sugarcane crops, especially susceptible varieties in large areas, contributes to high infection and spread of the disease. Our results agree with the finding that infection rates by smut tend to be higher in dry soils due to their suitability for teliospora survival.

Keywords : Monitoring, Sugarcane, Smut, Variety, PTPN X

2 INTRODUCTION Sugarcane smut is caused by the fungus Ustilago scitaminea (Sydow, 1924).

The first report of this disease incidence came from Natal, South Africa in 1877 as reported by (Luthra et al., 1940). The disease spread worldwide covering most of the sugarcane producing countries such as Mauritius, Rhodesia, Indonesia, etc (Heinz, 1987).

Recent reports show that short lived resistance could be attributed to pathogen genetic variability. A recent survey carried out in western Kenya showed that some susceptible varieties to smut in one location showed resistance in other locations (Kesref, 2002 in Nzioki et. al., 2010). Smut rating and ranking of the cultivars can vary significantly since host reaction to smut is influenced by the environment and probably races of the pathogen present (Lee-Lovick, 1978).

Studies by Hoy (1993) showed that Teliospores longevity was limited to 7 – 9 week in non-sterile soils with moisture levels ranging from 7 to 33%, but spores persisted only 4 weeks in contact with saturated soil. In India, the longevity of teliospores that buried in the field was limited to 3 weeks under wet conditions, whereas viable spores could be detected after 31 weeks under dry conditions).

Similar to other species of Ustilago, the sugarcane smut fungus also infects meristematic tissues. The fungus gains entry into the host exclusively through the bud scales (Fawcett, 1942).

Recently, smut is found in almost all of sugarcane area under PTPN X in Indonesia. Therefore monitoring of this disease on major cane varieties is needed.

This will assist in determining the range of varietal susceptibility to this disease and methods of management.

MATERIALS AND METHODS This research was conducted in all working areas of PTPN X in East Java covering Tulungagung, Blitar, Kediri, Jombang, Nganjuk, Bojonegoro, Mojokerto, Sidoarjo and Madura in August 2016 until April 2017. These localities cover all of the working area of PTPN X. The material used in this experiment included hand counter and stationery. The varieties observed were Bululawang, Kidang Kencono, PS 862, PS 881, PSDK 923, PS 864, VMC 71-16, PS 882, VMC 71-238, Cening, TLH 2, which are major varieties in each area.

The observation method was carried out by taking 10 samples of 10 m row with the row distance being 5 to 10 rows. Determination of row samples was chosen randomly. Smut symptoms were observed via the detection of the black “whip” structure of the apical growing point. Percent of smut infection was calculated by counting all stools that have smut symptoms and compared with healthy plants in the all rows. This observation was conducted on sugar cane aged 7 and 10 months

3

RESULT AND DISCUSSION Observation results in Sidoarjo, Jombang and Nganjuk areas showed that Bululawang varieties had the highest rates of smut infection compared to other varieties. Sidoarjo, Jombang and Nganjuk are similar sugarcane plantation areas.

There were irrigated land, and sugarcane plantation was separated by a long distance of other commodities such as paddy, maize and shallot. Sugarcane crop was not planted in one place for long period. Sugarcane farmers in Sidoarjo applied plant rotation system. Hence smut infection in this area was relatively lower than other areas. All of observations result can be seen in Table 1.

Sugarcane plantations in Tuban and Bojonegoro areas are mainly rainfed.

Sugarcane plantation was also separated by other commodities in a long distance.

Bululawang and PS 864 varieties are the most dominant varieties in Bojonegoro and Tuban. In the 10 months sugarcane old observation both varieties had relatively similar infection rates. This condition indicated that PS 864 and Bululawang had similar resistance levels to smut in Tuban and Bojonegoro area. However, further smut resistance tests are needed on the of PS 864 varieties.

Separation of sugarcane fields with other plantation and crop rotation system applied by sugarcane farmers affected the level of smut infection. Plant rotation affects spore survival hence reduces infection levels.

Different susceptible varieties were observed in Mojokerto, namely TLH 2. Our results showed that TLH 2 can be categorized as susceptible varieties to smut (Table 1). Bululawang and TLH 2 were major varieties in Mojokerto. At 7 months cane old observation, TLH 2 varieties had a very high infection rate compared to Bululawang variety. In case of 10 months cane, TLH 2 smut infection rate continued to increase up to 13.57%. There was no data of Bululawang variety infection rate at 10 months cane old because the cane has been harvested as a seed cane. Sugarcane plantation in Mojokerto is a vast expanse. Sugarcane is a main plantation which is planted continuously every year.

Bululawang, PS 881 and PS 862 are the major varieties in Pesantren Baru Sugar Factory. The highest smut infection was showed by Bululawang variety (12.55%), in the observation of 10 months sugarcane old. Similar observations were recorded in Tulungagung sugarcane areas. Bululawang variety has the highest smut infection rate compared to PS 862 and PS 881. This result demonstrates that Bululawang is a susceptible variety to smut.

4 Table 1. Percent of smut infection in 63 observed sugarcane fields District

Varieties

Smut infection on 7 months cane old (%)

Smut infection on 10 months cane old (%)

Sidoarjo

Bululawang PS 862 VMC 71-16 Kidang kencono

0 0 0.12 0

2.36 0 0.14 0.22

Jombang

Bululawang PS 862 PSDK923 PS 882

6.88 0 0 0

4.12 0 0 0

Nganjuk

Bululawang PS 862 PS 881

4.42 0 0

-

Bojonegoro & Bululawang Tuban PS 864

3.33 0.47

3.93 3.23

Mojokerto

Bululawang TLH2

0 8.94

13.57

Tulungagung

Bululawang PS 862 PS 881

0 0 0.17

16.81 2.19 1.58

Kediri

Bululawang PS 862 PS 881

0 0 2.10

12.55 1.64 3.36

Blitar (Ngadirejo SF)

Bululawang VMC 71-238 Cening PSDK 923

1.97 0 0 0

1.84 0 0 0

Blitar (Mrican SF)

Bululawang PS 862

12.42 0

18.14 2.96

Madura

Bululawang PS 864

12.42 0

27.31 0

The level of smut infection in Blitar sugarcane area was much lower than Kediri area and even in the same variety Bululawang. But a high percentage of smut infection occurred in Mrican Sugar Factory area in Blitar. This is probably due to the fact that both Pesantren Baru and Mrican SFs sugarcane plantation are rainfed areas. Dry soils are more suitable for teliospore survival (Hoy et al., 1993). In addition, sugar cane plants are always available and Bululawang variety is grown

5 over a large area. These factors resulted in the observed high smut infection rates in that region.

For Madura sugarcane area, observation was conducted in Pamekasan where sugarcane was planted continuously in rainfed areas. Bululawang variety was the main variety and almost 86.3% of sugarcane plantation were Bululawang variety.

This condition affected the high infection in the Madura region.

Bululawang variety is the most susceptible variety to smut compared to all varieties observed. This is seen from the percentage of smut infection rate in Bululawang which was higher than all varieties in all regions. On the other hand TLH 2 varieties showed a higher percentage of smut infection compared to Bululawang variety in Mojokerto. The TLH 2 variety needs to be tested in future trials. Madura, Kediri, Blitar and Tulungagung were the working area of PTPN X that showed smut infection levels higher than 10%. In all of these areas, the variety Bululawang constitutes more than 60% of the total number of varieties planted. Continuous availability of sugarcane crops, especially susceptible varieties in large areas, contributes to high smut infection and spread.

CONCLUSION Bululawang and TLH 2 varieties showed the highest susceptibility to smut infection compared to all varieties observed. Continuous availability of sugarcane crops, especially susceptible varieties in large areas, contributes to high smut infection and spread. Smut infection rates tend to be higher in dry land due to its suitability for teliospora survival.

ACKNOWLEDGEMENTS The authors would like to thank the Board of Directors of PTPN X for supporting and funding this research.

REFERENCES Heinz, D.J. (1987). Sugarcane improvement through breeding. Elsevier Publications, pp. 455-502 Hisieh WH, Lee CS (1978). Compatibility and pathogenicity of two races of Ustilago scitaminea Sydow in Taiwan. Taiwan Sugar, 25: 46-48.

Hoy, J. W., Zheng, J.,Grelen, L. B., and Geaghan, J. P. (1993). Longevity of Teliospores of Ustilago scitaminea in Soil. Plant dis. 77:393-397 Fawcett GL (1942) circular, Estacion Experimental Agricola, Tucuman,PP.114

6 Nzioki, H. S., J. E. Jamoza, C. O. Olweny* and J. K. Rono. (2010). Characterization of physiologic races of sugarcane smut (Ustilago scitaminea) in Kenya. African Journal of Microbiology Research. 4(16): 1694-1697